Imaging

A morbidly obese 54-year-old woman presented to the emergency department after experiencing generalized abdominal pain for 3 days. She rated the pain as 5 on a scale of 10 and described it as dull, cramping, waxing and waning, not radiating, and not relieved with changes of position—in fact, not alleviated by anything she had tried. Her pain was associated with nausea and 1 episode of vomiting. She also experienced constipation before the onset of pain.

She denied recent trauma, recent travel, diarrhea, fevers, weakness, shortness of breath, chest pain, other muscle pains, or recent changes in diet. She also denied having this pain in the past. She said she had unintentionally lost some weight but was not certain how much. She denied tobacco, alcohol, or illicit drug use. She had no history of surgery.

Her medical history included hypertension, anemia, and uterine fibroids. Her current medications included losartan, hydrochlorothiazide, and albuterol. She had no family history of significant disease.

INITIAL EVALUATION AND MANAGEMENT

On admission, her temperature was 97.8°F (36.6°C), heart rate 100 beats per minute, blood pressure 136/64 mm Hg, respiratory rate 18 breaths per minute, oxygen saturation 97% on room air, weight 130.6 kg, and body mass index 35 kg/m².

She was alert and oriented to person, place, and time. She was in mild discomfort but no distress. Her lungs were clear to auscultation, with no wheezing or crackles. Heart rate and rhythm were regular, with no extra heart sounds or murmurs. Bowel sounds were normal in all 4 quadrants, with tenderness to palpation of the epigastric area, but with no guarding or rebound tenderness.

Laboratory test results

Notable results of blood testing at presentation were as follows:

• Hemoglobin 8.2 g/dL (reference range 12.3–15.3)
• Hematocrit 26% (41–50)
• Mean corpuscular volume 107 fL (80–100)
• Blood urea nitrogen 33 mg/dL (8–21); 6 months earlier it was 16
• Serum creatinine 3.6 mg/dL (0.58–0.96); 6 months earlier, it was 0.75
• Albumin 3.3 g/dL (3.5–5)
• Calcium 18.4 mg/dL (8.4–10.2); 6 months earlier, it was 9.6
• Corrected calcium 19 mg/dL.

Findings on imaging, electrocardiography

Chest radiography showed no acute cardiopulmonary abnormalities. Abdominal computed tomography without contrast showed no abnormalities within the pancreas and no evidence of inflammation or obstruction. Electrocardiography showed sinus tachycardia.

DIFFERENTIAL DIAGNOSIS

1. Which is the most likely cause of this patient’s symptoms?

• Primary hyperparathyroidism
• Malignancy
• Her drug therapy
• Familial hypercalcemic hypocalciuria

In total, her laboratory results were consistent with macrocytic anemia, severe hypercalcemia, and acute kidney injury, and she had generalized symptoms.

Primary hyperparathyroidism

A main cause of hypercalcemia is primary hyperparathyroidism, and this needs to be ruled out. Benign adenomas are the most common cause of primary hyperparathyroidism, and a risk factor for benign adenoma is exposure to therapeutic levels of radiation.³

In hyperparathyroidism, there is an increased secretion of parathyroid hormone (PTH), which has multiple effects including increased reabsorption of calcium from the urine, increased excretion of phosphate, and increased expression of 1,25-hydroxyvitamin D hydroxylase to activate vitamin D. PTH also stimulates osteoclasts to increase their expression of receptor activator of nuclear factor kappa B ligand (RANKL), which has a downstream effect on osteoclast precursors to cause bone reabsorption.³

Inherited primary hyperparathyroidism tends to present at a younger age, with multiple overactive parathyroid glands.³ Given our patient’s age, inherited primary hyparathyroidism is thus less likely.

The probability that malignancy is causing the hypercalcemia increases with calcium levels greater than 13 mg/dL. Epidemiologically, in hospitalized patients with hypercalcemia, the source tends to be malignancy.⁴ Typically, patients who develop hypercalcemia from malignancy have a worse prognosis.⁵

Solid tumors and leukemias can cause hypercalcemia. The mechanisms include humoral factors secreted by the malignancy, local osteolysis due to tumor invasion of bone, and excessive absorption of calcium due to excess vitamin D produced by malignancies.⁵ The cancers that most frequently cause an increase in calcium resorption are lung cancer, renal cancer, breast cancer, and multiple myeloma.¹

Solid tumors with no bone metastasis and non-Hodgkin lymphoma that release PTH-related protein (PTHrP) cause humoral hypercalcemia in malignancy. The patient is typically in an advanced stage of disease. PTHrP increases serum calcium levels by decreasing the kidney’s ability to excrete calcium and by increasing bone turnover. It has no effect on intestinal absorption because of its inability to stimulate activated vitamin D₃. Thus, the increase in systemic calcium comes directly from breakdown of bone and inability to excrete the excess.

PTHrP has a unique role in breast cancer: it is released locally in areas where cancer cells have metastasized to bone, but it does not cause a systemic effect. Bone resorption occurs in areas of metastasis and results from an increase in expression of RANKL and RANK in osteoclasts in response to the effects of PTHrP, leading to an increase in the production of osteoclastic cells.¹

Tamoxifen, an endocrine therapy often used in breast cancer, also causes a release of bone-reabsorbing factors from tumor cells, which can partially contribute to hypercal­cemia.⁵

Myeloma cells secrete RANKL, which stimulates osteoclastic activity, and they also  release interleukin 6 (IL-6) and activating macrophage inflammatory protein alpha. Serum testing usually shows low or normal intact PTH, PTHrP, and 1,25-dihydroxyvitamin D.¹

Patients with multiple myeloma have a worse prognosis if they have a high red blood cell distribution width, a condition shown to correlate with malnutrition, leading to deficiencies in vitamin B₁₂ and to poor response to treatment.⁶ Up to 14% of patients with multiple myeloma have vitamin B₁₂ deficiency.⁷

Our patient’s recent weight loss and severe hypercalcemia raise suspicion of malignancy. Further, her obesity makes proper routine breast examination difficult and thus increases the chance of undiagnosed breast cancer.⁸ Her decrease in renal function and her anemia complicated by hypercalcemia also raise suspicion of multiple myeloma.

Hypercalcemia due to drug therapy

Thiazide diuretics, lithium, teriparatide, and vitamin A in excessive amounts can raise the serum calcium concentration.⁵ Our patient was taking a thiazide for hypertension, but her extremely high calcium level places drug-induced hypercalcemia as the sole cause lower on the differential list.

Familial hypercalcemic hypocalciuria

Familial hypercalcemic hypocalciuria is a rare autosomal-dominant cause of hypercalcemia in which the ability of the body (and especially the kidneys) to sense levels of calcium is impaired, leading to a decrease in excretion of calcium in the urine.³ Very high calcium levels are rare in hypercalcemic hypocalciuria.³ In our patient with a corrected calcium concentration of nearly 19 mg/dL, familial hypercalcemic hypocalciuria is very unlikely to be the cause of the hypercalcemia.

WHAT ARE THE NEXT STEPS IN THE WORKUP?

As hypercalcemia has been confirmed, the intact PTH level should be checked to determine whether the patient’s condition is PTH-mediated. If the PTH level is in the upper range of normal or is minimally elevated, primary hyperparathyroidism is likely. Elevated PTH confirms primary hyperparathyroidism. A low-normal or low intact PTH confirms a non-PTH-mediated process, and once this is confirmed, PTHrP levels should be checked. An elevated PTHrP suggests humoral hypercalcemia of malignancy. Serum protein electrophoresis, urine protein electrophoresis, and a serum light chain assay should be performed to rule out multiple myeloma.

Vitamin D toxicity is associated with high concentrations of 1,25-dihydroxyvitamin D and 25-hydroxyvitamin D metabolites. These levels should be checked in this patient.

Other disorders that cause hypercalcemia are vitamin A toxicity and hyperthyroidism, so vitamin A and thyroid-stimulating hormone levels should also be checked.⁵

CASE CONTINUED

After further questioning, the patient said that she had had lower back pain about 1 to 2 weeks before coming to the emergency room; her primary care doctor had said the pain was likely from muscle strain. The pain had almost resolved but was still present.

The results of further laboratory testing were as follows:

• Serum PTH 11 pg/mL (15–65)
• PTHrP 3.4 pmol/L (< 2.0)
• Protein electrophoresis showed a monoclonal (M) spike of 0.2 g/dL (0)
• Activated vitamin D < 5 ng/mL (19.9–79.3)
• Vitamin A 7.2 mg/dL (33.1–100)
• Vitamin B₁₂ 194 pg/mL (239–931)
• Thyroid-stimulating hormone 1.21 mIU/ L (0.47–4.68
• Free thyroxine 1.27 ng/dL (0.78–2.19)
• Iron 103 µg/dL (37–170)
• Total iron-binding capacity 335 µg/dL (265–497)
• Transferrin 248 mg/dL (206–381)
• Ferritin 66 ng/mL (11.1–264)
• Urine protein (random) 100 mg/dL (0–20)
• Urine microalbumin (random) 5.9 mg/dL (0–1.6)
• Urine creatinine clearance 88.5 mL/min (88–128)
• Urine albumin-creatinine ratio 66.66 mg/g (< 30).

A nuclear bone scan showed increased bone uptake in the hip and both shoulders, consistent with arthritis, and increased activity in 2 of the lower left ribs, associated with rib fractures secondary to lytic lesions. A skeletal survey at a later date showed multiple well-circumscribed “punched-out” lytic lesions in both forearms and both femurs.

2. What should be the next step in this patient’s management?

• Intravenous (IV) fluids
• Calcitonin
• Bisphosphonate treatment
• Denosumab
• Hemodialysis

Initial treatment of severe hypercalcemia includes the following:

Start IV isotonic fluids at a rate of 150 mL/h (if the patient is making urine) to maintain urine output at more than 100 mL/h. Closely monitor urine output.

Give calcitonin 4 IU/kg in combination with IV fluids to reduce calcium levels within the first 12 to 48 hours of treatment.

Give a bisphosphonate, eg, zoledronic acid 4 mg over 15 minutes, or pamidronate 60 to 90 mg over 2 hours. Zoledronic acid is preferred in malignancy-induced hypercal­cemia because it is more potent. Doses should be adjusted in patients with renal failure.

Give denosumab if hypercalcemia is refractory to bisphosphonates, or when bisphosphonates cannot be used in renal failure.⁹

Hemodialysis is performed in patients who have significant neurologic symptoms irrespective of acute renal insufficiency.

Our patient was started on 0.9% sodium chloride at a rate of 150 mL/h for severe hypercalcemia. Zoledronic acid 4 mg IV was given once. These measures lowered her calcium level and lessened her acute kidney injury.

ADDITIONAL FINDINGS

Urine testing was positive for Bence Jones protein. Immune electrophoresis, performed because of suspicion of multiple myeloma, showed an elevated level of kappa light chains at 806.7 mg/dL (0.33–1.94) and normal lambda light chains at 0.62 mg/dL (0.57–2.63). The immunoglobulin G level was low at 496 mg/dL (610–1,660). In patients with severe hypercalcemia, these results point to a diagnosis of malignancy. Bone marrow aspiration study showed greater than 10% plasma cells, confirming multiple myeloma.

MULTIPLE MYELOMA

The diagnosis of multiple myeloma is based in part on the presence of 10% or more of clonal bone marrow plasma cells¹⁰ and of specific end-organ damage (anemia, hypercalcemia, renal insufficiency, or bone lesions).⁹

Bone marrow clonality can be shown by the ratio of kappa to lambda light chains as  detected with immunohistochemistry, immunofluorescence, or flow cytometry.11 The normal ratio is 0.26 to 1.65 for a patient with normal kidney function. In this patient, however, the ratio was 1,301.08 (806.67 kappa to 0.62 lambda), which was extremely out of range. The patient’s bone marrow biopsy results revealed the presence of 15% clonal bone marrow plasma cells.

Multiple myeloma causes osteolytic lesions through increased activation of osteoclast activating factor that stimulates the growth of osteoclast precursors. At the same time, it inhibits osteoblast formation via multiple pathways, including the action of sclerostin.¹¹ Our patient had lytic lesions in 2 left lower ribs and in both forearms and femurs.

Hypercalcemia in multiple myeloma is attributed to 2 main factors: bone breakdown and macrophage overactivation. Multiple myeloma cells increase the release of macrophage inflammatory protein 1-alpha and tumor necrosis factor, which are inflammatory proteins that cause an increase in macrophages, which cause an increase in calcitriol.¹¹ As noted, our patient’s calcium level at presentation was 18.4 mg/dL uncorrected and 18.96 mg/dL corrected.

Cast nephropathy can occur in the distal tubules from the increased free light chains circulating and combining with Tamm-Horsfall protein, which in turn causes obstruction and local inflammation,¹² leading to a rise in creatinine levels and resulting in acute kidney injury,¹² as in our patient.

TREATMENT CONSIDERATIONS IN MULTIPLE MYELOMA

Our patient was referred to an oncologist for management.

In the management of multiple myeloma, the patient’s quality of life needs to be considered. With the development of new agents to combat the damages of the osteolytic effects, there is hope for improving quality of life.^13,14 New agents under study include anabolic agents such as antisclerostin and anti-Dickkopf-1, which promote osteoblastogenesis, leading to bone formation, with the possibility of repairing existing damage.¹⁵

TAKE-HOME POINTS

• If hypercalcemia is mild to moderate, consider primary hyperparathyroidism.
• Identify patients with severe symptoms of hypercalcemia such as volume depletion, acute kidney injury, arrhythmia, or seizures.
• Confirm severe cases of hypercalcemia and treat severe cases effectively.
• Severe hypercalcemia may need further investigation into a potential underlying malignancy.

A morbidly obese 54-year-old woman presented to the emergency department after experiencing generalized abdominal pain for 3 days. She rated the pain as 5 on a scale of 10 and described it as dull, cramping, waxing and waning, not radiating, and not relieved with changes of position—in fact, not alleviated by anything she had tried. Her pain was associated with nausea and 1 episode of vomiting. She also experienced constipation before the onset of pain.

She denied recent trauma, recent travel, diarrhea, fevers, weakness, shortness of breath, chest pain, other muscle pains, or recent changes in diet. She also denied having this pain in the past. She said she had unintentionally lost some weight but was not certain how much. She denied tobacco, alcohol, or illicit drug use. She had no history of surgery.

Her medical history included hypertension, anemia, and uterine fibroids. Her current medications included losartan, hydrochlorothiazide, and albuterol. She had no family history of significant disease.

INITIAL EVALUATION AND MANAGEMENT

On admission, her temperature was 97.8°F (36.6°C), heart rate 100 beats per minute, blood pressure 136/64 mm Hg, respiratory rate 18 breaths per minute, oxygen saturation 97% on room air, weight 130.6 kg, and body mass index 35 kg/m².

She was alert and oriented to person, place, and time. She was in mild discomfort but no distress. Her lungs were clear to auscultation, with no wheezing or crackles. Heart rate and rhythm were regular, with no extra heart sounds or murmurs. Bowel sounds were normal in all 4 quadrants, with tenderness to palpation of the epigastric area, but with no guarding or rebound tenderness.

Laboratory test results

Notable results of blood testing at presentation were as follows:

• Hemoglobin 8.2 g/dL (reference range 12.3–15.3)
• Hematocrit 26% (41–50)
• Mean corpuscular volume 107 fL (80–100)
• Blood urea nitrogen 33 mg/dL (8–21); 6 months earlier it was 16
• Serum creatinine 3.6 mg/dL (0.58–0.96); 6 months earlier, it was 0.75
• Albumin 3.3 g/dL (3.5–5)
• Calcium 18.4 mg/dL (8.4–10.2); 6 months earlier, it was 9.6
• Corrected calcium 19 mg/dL.

Findings on imaging, electrocardiography

Chest radiography showed no acute cardiopulmonary abnormalities. Abdominal computed tomography without contrast showed no abnormalities within the pancreas and no evidence of inflammation or obstruction. Electrocardiography showed sinus tachycardia.

DIFFERENTIAL DIAGNOSIS

1. Which is the most likely cause of this patient’s symptoms?

• Primary hyperparathyroidism
• Malignancy
• Her drug therapy
• Familial hypercalcemic hypocalciuria

In total, her laboratory results were consistent with macrocytic anemia, severe hypercalcemia, and acute kidney injury, and she had generalized symptoms.

Primary hyperparathyroidism

A main cause of hypercalcemia is primary hyperparathyroidism, and this needs to be ruled out. Benign adenomas are the most common cause of primary hyperparathyroidism, and a risk factor for benign adenoma is exposure to therapeutic levels of radiation.³

In hyperparathyroidism, there is an increased secretion of parathyroid hormone (PTH), which has multiple effects including increased reabsorption of calcium from the urine, increased excretion of phosphate, and increased expression of 1,25-hydroxyvitamin D hydroxylase to activate vitamin D. PTH also stimulates osteoclasts to increase their expression of receptor activator of nuclear factor kappa B ligand (RANKL), which has a downstream effect on osteoclast precursors to cause bone reabsorption.³

Inherited primary hyperparathyroidism tends to present at a younger age, with multiple overactive parathyroid glands.³ Given our patient’s age, inherited primary hyparathyroidism is thus less likely.

The probability that malignancy is causing the hypercalcemia increases with calcium levels greater than 13 mg/dL. Epidemiologically, in hospitalized patients with hypercalcemia, the source tends to be malignancy.⁴ Typically, patients who develop hypercalcemia from malignancy have a worse prognosis.⁵

Solid tumors and leukemias can cause hypercalcemia. The mechanisms include humoral factors secreted by the malignancy, local osteolysis due to tumor invasion of bone, and excessive absorption of calcium due to excess vitamin D produced by malignancies.⁵ The cancers that most frequently cause an increase in calcium resorption are lung cancer, renal cancer, breast cancer, and multiple myeloma.¹

Solid tumors with no bone metastasis and non-Hodgkin lymphoma that release PTH-related protein (PTHrP) cause humoral hypercalcemia in malignancy. The patient is typically in an advanced stage of disease. PTHrP increases serum calcium levels by decreasing the kidney’s ability to excrete calcium and by increasing bone turnover. It has no effect on intestinal absorption because of its inability to stimulate activated vitamin D₃. Thus, the increase in systemic calcium comes directly from breakdown of bone and inability to excrete the excess.

PTHrP has a unique role in breast cancer: it is released locally in areas where cancer cells have metastasized to bone, but it does not cause a systemic effect. Bone resorption occurs in areas of metastasis and results from an increase in expression of RANKL and RANK in osteoclasts in response to the effects of PTHrP, leading to an increase in the production of osteoclastic cells.¹

Tamoxifen, an endocrine therapy often used in breast cancer, also causes a release of bone-reabsorbing factors from tumor cells, which can partially contribute to hypercal­cemia.⁵

Myeloma cells secrete RANKL, which stimulates osteoclastic activity, and they also  release interleukin 6 (IL-6) and activating macrophage inflammatory protein alpha. Serum testing usually shows low or normal intact PTH, PTHrP, and 1,25-dihydroxyvitamin D.¹

Patients with multiple myeloma have a worse prognosis if they have a high red blood cell distribution width, a condition shown to correlate with malnutrition, leading to deficiencies in vitamin B₁₂ and to poor response to treatment.⁶ Up to 14% of patients with multiple myeloma have vitamin B₁₂ deficiency.⁷

Our patient’s recent weight loss and severe hypercalcemia raise suspicion of malignancy. Further, her obesity makes proper routine breast examination difficult and thus increases the chance of undiagnosed breast cancer.⁸ Her decrease in renal function and her anemia complicated by hypercalcemia also raise suspicion of multiple myeloma.

Hypercalcemia due to drug therapy

Thiazide diuretics, lithium, teriparatide, and vitamin A in excessive amounts can raise the serum calcium concentration.⁵ Our patient was taking a thiazide for hypertension, but her extremely high calcium level places drug-induced hypercalcemia as the sole cause lower on the differential list.

Familial hypercalcemic hypocalciuria

Familial hypercalcemic hypocalciuria is a rare autosomal-dominant cause of hypercalcemia in which the ability of the body (and especially the kidneys) to sense levels of calcium is impaired, leading to a decrease in excretion of calcium in the urine.³ Very high calcium levels are rare in hypercalcemic hypocalciuria.³ In our patient with a corrected calcium concentration of nearly 19 mg/dL, familial hypercalcemic hypocalciuria is very unlikely to be the cause of the hypercalcemia.

WHAT ARE THE NEXT STEPS IN THE WORKUP?

As hypercalcemia has been confirmed, the intact PTH level should be checked to determine whether the patient’s condition is PTH-mediated. If the PTH level is in the upper range of normal or is minimally elevated, primary hyperparathyroidism is likely. Elevated PTH confirms primary hyperparathyroidism. A low-normal or low intact PTH confirms a non-PTH-mediated process, and once this is confirmed, PTHrP levels should be checked. An elevated PTHrP suggests humoral hypercalcemia of malignancy. Serum protein electrophoresis, urine protein electrophoresis, and a serum light chain assay should be performed to rule out multiple myeloma.

Vitamin D toxicity is associated with high concentrations of 1,25-dihydroxyvitamin D and 25-hydroxyvitamin D metabolites. These levels should be checked in this patient.

Other disorders that cause hypercalcemia are vitamin A toxicity and hyperthyroidism, so vitamin A and thyroid-stimulating hormone levels should also be checked.⁵

CASE CONTINUED

After further questioning, the patient said that she had had lower back pain about 1 to 2 weeks before coming to the emergency room; her primary care doctor had said the pain was likely from muscle strain. The pain had almost resolved but was still present.

The results of further laboratory testing were as follows:

• Serum PTH 11 pg/mL (15–65)
• PTHrP 3.4 pmol/L (< 2.0)
• Protein electrophoresis showed a monoclonal (M) spike of 0.2 g/dL (0)
• Activated vitamin D < 5 ng/mL (19.9–79.3)
• Vitamin A 7.2 mg/dL (33.1–100)
• Vitamin B₁₂ 194 pg/mL (239–931)
• Thyroid-stimulating hormone 1.21 mIU/ L (0.47–4.68
• Free thyroxine 1.27 ng/dL (0.78–2.19)
• Iron 103 µg/dL (37–170)
• Total iron-binding capacity 335 µg/dL (265–497)
• Transferrin 248 mg/dL (206–381)
• Ferritin 66 ng/mL (11.1–264)
• Urine protein (random) 100 mg/dL (0–20)
• Urine microalbumin (random) 5.9 mg/dL (0–1.6)
• Urine creatinine clearance 88.5 mL/min (88–128)
• Urine albumin-creatinine ratio 66.66 mg/g (< 30).

A nuclear bone scan showed increased bone uptake in the hip and both shoulders, consistent with arthritis, and increased activity in 2 of the lower left ribs, associated with rib fractures secondary to lytic lesions. A skeletal survey at a later date showed multiple well-circumscribed “punched-out” lytic lesions in both forearms and both femurs.

2. What should be the next step in this patient’s management?

• Intravenous (IV) fluids
• Calcitonin
• Bisphosphonate treatment
• Denosumab
• Hemodialysis

Initial treatment of severe hypercalcemia includes the following:

Start IV isotonic fluids at a rate of 150 mL/h (if the patient is making urine) to maintain urine output at more than 100 mL/h. Closely monitor urine output.

Give calcitonin 4 IU/kg in combination with IV fluids to reduce calcium levels within the first 12 to 48 hours of treatment.

Give a bisphosphonate, eg, zoledronic acid 4 mg over 15 minutes, or pamidronate 60 to 90 mg over 2 hours. Zoledronic acid is preferred in malignancy-induced hypercal­cemia because it is more potent. Doses should be adjusted in patients with renal failure.

Give denosumab if hypercalcemia is refractory to bisphosphonates, or when bisphosphonates cannot be used in renal failure.⁹

Hemodialysis is performed in patients who have significant neurologic symptoms irrespective of acute renal insufficiency.

Our patient was started on 0.9% sodium chloride at a rate of 150 mL/h for severe hypercalcemia. Zoledronic acid 4 mg IV was given once. These measures lowered her calcium level and lessened her acute kidney injury.

ADDITIONAL FINDINGS

Urine testing was positive for Bence Jones protein. Immune electrophoresis, performed because of suspicion of multiple myeloma, showed an elevated level of kappa light chains at 806.7 mg/dL (0.33–1.94) and normal lambda light chains at 0.62 mg/dL (0.57–2.63). The immunoglobulin G level was low at 496 mg/dL (610–1,660). In patients with severe hypercalcemia, these results point to a diagnosis of malignancy. Bone marrow aspiration study showed greater than 10% plasma cells, confirming multiple myeloma.

MULTIPLE MYELOMA

The diagnosis of multiple myeloma is based in part on the presence of 10% or more of clonal bone marrow plasma cells¹⁰ and of specific end-organ damage (anemia, hypercalcemia, renal insufficiency, or bone lesions).⁹

Bone marrow clonality can be shown by the ratio of kappa to lambda light chains as  detected with immunohistochemistry, immunofluorescence, or flow cytometry.11 The normal ratio is 0.26 to 1.65 for a patient with normal kidney function. In this patient, however, the ratio was 1,301.08 (806.67 kappa to 0.62 lambda), which was extremely out of range. The patient’s bone marrow biopsy results revealed the presence of 15% clonal bone marrow plasma cells.

Multiple myeloma causes osteolytic lesions through increased activation of osteoclast activating factor that stimulates the growth of osteoclast precursors. At the same time, it inhibits osteoblast formation via multiple pathways, including the action of sclerostin.¹¹ Our patient had lytic lesions in 2 left lower ribs and in both forearms and femurs.

Hypercalcemia in multiple myeloma is attributed to 2 main factors: bone breakdown and macrophage overactivation. Multiple myeloma cells increase the release of macrophage inflammatory protein 1-alpha and tumor necrosis factor, which are inflammatory proteins that cause an increase in macrophages, which cause an increase in calcitriol.¹¹ As noted, our patient’s calcium level at presentation was 18.4 mg/dL uncorrected and 18.96 mg/dL corrected.

Cast nephropathy can occur in the distal tubules from the increased free light chains circulating and combining with Tamm-Horsfall protein, which in turn causes obstruction and local inflammation,¹² leading to a rise in creatinine levels and resulting in acute kidney injury,¹² as in our patient.

TREATMENT CONSIDERATIONS IN MULTIPLE MYELOMA

Our patient was referred to an oncologist for management.

In the management of multiple myeloma, the patient’s quality of life needs to be considered. With the development of new agents to combat the damages of the osteolytic effects, there is hope for improving quality of life.^13,14 New agents under study include anabolic agents such as antisclerostin and anti-Dickkopf-1, which promote osteoblastogenesis, leading to bone formation, with the possibility of repairing existing damage.¹⁵

TAKE-HOME POINTS

• If hypercalcemia is mild to moderate, consider primary hyperparathyroidism.
• Identify patients with severe symptoms of hypercalcemia such as volume depletion, acute kidney injury, arrhythmia, or seizures.
• Confirm severe cases of hypercalcemia and treat severe cases effectively.
• Severe hypercalcemia may need further investigation into a potential underlying malignancy.

A morbidly obese 54-year-old woman presented to the emergency department after experiencing generalized abdominal pain for 3 days. She rated the pain as 5 on a scale of 10 and described it as dull, cramping, waxing and waning, not radiating, and not relieved with changes of position—in fact, not alleviated by anything she had tried. Her pain was associated with nausea and 1 episode of vomiting. She also experienced constipation before the onset of pain.

She denied recent trauma, recent travel, diarrhea, fevers, weakness, shortness of breath, chest pain, other muscle pains, or recent changes in diet. She also denied having this pain in the past. She said she had unintentionally lost some weight but was not certain how much. She denied tobacco, alcohol, or illicit drug use. She had no history of surgery.

Her medical history included hypertension, anemia, and uterine fibroids. Her current medications included losartan, hydrochlorothiazide, and albuterol. She had no family history of significant disease.

INITIAL EVALUATION AND MANAGEMENT

On admission, her temperature was 97.8°F (36.6°C), heart rate 100 beats per minute, blood pressure 136/64 mm Hg, respiratory rate 18 breaths per minute, oxygen saturation 97% on room air, weight 130.6 kg, and body mass index 35 kg/m².

She was alert and oriented to person, place, and time. She was in mild discomfort but no distress. Her lungs were clear to auscultation, with no wheezing or crackles. Heart rate and rhythm were regular, with no extra heart sounds or murmurs. Bowel sounds were normal in all 4 quadrants, with tenderness to palpation of the epigastric area, but with no guarding or rebound tenderness.

Laboratory test results

Notable results of blood testing at presentation were as follows:

• Hemoglobin 8.2 g/dL (reference range 12.3–15.3)
• Hematocrit 26% (41–50)
• Mean corpuscular volume 107 fL (80–100)
• Blood urea nitrogen 33 mg/dL (8–21); 6 months earlier it was 16
• Serum creatinine 3.6 mg/dL (0.58–0.96); 6 months earlier, it was 0.75
• Albumin 3.3 g/dL (3.5–5)
• Calcium 18.4 mg/dL (8.4–10.2); 6 months earlier, it was 9.6
• Corrected calcium 19 mg/dL.

Findings on imaging, electrocardiography

Chest radiography showed no acute cardiopulmonary abnormalities. Abdominal computed tomography without contrast showed no abnormalities within the pancreas and no evidence of inflammation or obstruction. Electrocardiography showed sinus tachycardia.

DIFFERENTIAL DIAGNOSIS

1. Which is the most likely cause of this patient’s symptoms?

• Primary hyperparathyroidism
• Malignancy
• Her drug therapy
• Familial hypercalcemic hypocalciuria

In total, her laboratory results were consistent with macrocytic anemia, severe hypercalcemia, and acute kidney injury, and she had generalized symptoms.

Primary hyperparathyroidism

A main cause of hypercalcemia is primary hyperparathyroidism, and this needs to be ruled out. Benign adenomas are the most common cause of primary hyperparathyroidism, and a risk factor for benign adenoma is exposure to therapeutic levels of radiation.³

In hyperparathyroidism, there is an increased secretion of parathyroid hormone (PTH), which has multiple effects including increased reabsorption of calcium from the urine, increased excretion of phosphate, and increased expression of 1,25-hydroxyvitamin D hydroxylase to activate vitamin D. PTH also stimulates osteoclasts to increase their expression of receptor activator of nuclear factor kappa B ligand (RANKL), which has a downstream effect on osteoclast precursors to cause bone reabsorption.³

Inherited primary hyperparathyroidism tends to present at a younger age, with multiple overactive parathyroid glands.³ Given our patient’s age, inherited primary hyparathyroidism is thus less likely.

The probability that malignancy is causing the hypercalcemia increases with calcium levels greater than 13 mg/dL. Epidemiologically, in hospitalized patients with hypercalcemia, the source tends to be malignancy.⁴ Typically, patients who develop hypercalcemia from malignancy have a worse prognosis.⁵

Solid tumors and leukemias can cause hypercalcemia. The mechanisms include humoral factors secreted by the malignancy, local osteolysis due to tumor invasion of bone, and excessive absorption of calcium due to excess vitamin D produced by malignancies.⁵ The cancers that most frequently cause an increase in calcium resorption are lung cancer, renal cancer, breast cancer, and multiple myeloma.¹

Solid tumors with no bone metastasis and non-Hodgkin lymphoma that release PTH-related protein (PTHrP) cause humoral hypercalcemia in malignancy. The patient is typically in an advanced stage of disease. PTHrP increases serum calcium levels by decreasing the kidney’s ability to excrete calcium and by increasing bone turnover. It has no effect on intestinal absorption because of its inability to stimulate activated vitamin D₃. Thus, the increase in systemic calcium comes directly from breakdown of bone and inability to excrete the excess.

PTHrP has a unique role in breast cancer: it is released locally in areas where cancer cells have metastasized to bone, but it does not cause a systemic effect. Bone resorption occurs in areas of metastasis and results from an increase in expression of RANKL and RANK in osteoclasts in response to the effects of PTHrP, leading to an increase in the production of osteoclastic cells.¹

Tamoxifen, an endocrine therapy often used in breast cancer, also causes a release of bone-reabsorbing factors from tumor cells, which can partially contribute to hypercal­cemia.⁵

Myeloma cells secrete RANKL, which stimulates osteoclastic activity, and they also  release interleukin 6 (IL-6) and activating macrophage inflammatory protein alpha. Serum testing usually shows low or normal intact PTH, PTHrP, and 1,25-dihydroxyvitamin D.¹

Patients with multiple myeloma have a worse prognosis if they have a high red blood cell distribution width, a condition shown to correlate with malnutrition, leading to deficiencies in vitamin B₁₂ and to poor response to treatment.⁶ Up to 14% of patients with multiple myeloma have vitamin B₁₂ deficiency.⁷

Our patient’s recent weight loss and severe hypercalcemia raise suspicion of malignancy. Further, her obesity makes proper routine breast examination difficult and thus increases the chance of undiagnosed breast cancer.⁸ Her decrease in renal function and her anemia complicated by hypercalcemia also raise suspicion of multiple myeloma.

Hypercalcemia due to drug therapy

Thiazide diuretics, lithium, teriparatide, and vitamin A in excessive amounts can raise the serum calcium concentration.⁵ Our patient was taking a thiazide for hypertension, but her extremely high calcium level places drug-induced hypercalcemia as the sole cause lower on the differential list.

Familial hypercalcemic hypocalciuria

Familial hypercalcemic hypocalciuria is a rare autosomal-dominant cause of hypercalcemia in which the ability of the body (and especially the kidneys) to sense levels of calcium is impaired, leading to a decrease in excretion of calcium in the urine.³ Very high calcium levels are rare in hypercalcemic hypocalciuria.³ In our patient with a corrected calcium concentration of nearly 19 mg/dL, familial hypercalcemic hypocalciuria is very unlikely to be the cause of the hypercalcemia.

WHAT ARE THE NEXT STEPS IN THE WORKUP?

As hypercalcemia has been confirmed, the intact PTH level should be checked to determine whether the patient’s condition is PTH-mediated. If the PTH level is in the upper range of normal or is minimally elevated, primary hyperparathyroidism is likely. Elevated PTH confirms primary hyperparathyroidism. A low-normal or low intact PTH confirms a non-PTH-mediated process, and once this is confirmed, PTHrP levels should be checked. An elevated PTHrP suggests humoral hypercalcemia of malignancy. Serum protein electrophoresis, urine protein electrophoresis, and a serum light chain assay should be performed to rule out multiple myeloma.

Vitamin D toxicity is associated with high concentrations of 1,25-dihydroxyvitamin D and 25-hydroxyvitamin D metabolites. These levels should be checked in this patient.

Other disorders that cause hypercalcemia are vitamin A toxicity and hyperthyroidism, so vitamin A and thyroid-stimulating hormone levels should also be checked.⁵

CASE CONTINUED

After further questioning, the patient said that she had had lower back pain about 1 to 2 weeks before coming to the emergency room; her primary care doctor had said the pain was likely from muscle strain. The pain had almost resolved but was still present.

The results of further laboratory testing were as follows:

• Serum PTH 11 pg/mL (15–65)
• PTHrP 3.4 pmol/L (< 2.0)
• Protein electrophoresis showed a monoclonal (M) spike of 0.2 g/dL (0)
• Activated vitamin D < 5 ng/mL (19.9–79.3)
• Vitamin A 7.2 mg/dL (33.1–100)
• Vitamin B₁₂ 194 pg/mL (239–931)
• Thyroid-stimulating hormone 1.21 mIU/ L (0.47–4.68
• Free thyroxine 1.27 ng/dL (0.78–2.19)
• Iron 103 µg/dL (37–170)
• Total iron-binding capacity 335 µg/dL (265–497)
• Transferrin 248 mg/dL (206–381)
• Ferritin 66 ng/mL (11.1–264)
• Urine protein (random) 100 mg/dL (0–20)
• Urine microalbumin (random) 5.9 mg/dL (0–1.6)
• Urine creatinine clearance 88.5 mL/min (88–128)
• Urine albumin-creatinine ratio 66.66 mg/g (< 30).

A nuclear bone scan showed increased bone uptake in the hip and both shoulders, consistent with arthritis, and increased activity in 2 of the lower left ribs, associated with rib fractures secondary to lytic lesions. A skeletal survey at a later date showed multiple well-circumscribed “punched-out” lytic lesions in both forearms and both femurs.

2. What should be the next step in this patient’s management?

• Intravenous (IV) fluids
• Calcitonin
• Bisphosphonate treatment
• Denosumab
• Hemodialysis

Initial treatment of severe hypercalcemia includes the following:

Start IV isotonic fluids at a rate of 150 mL/h (if the patient is making urine) to maintain urine output at more than 100 mL/h. Closely monitor urine output.

Give calcitonin 4 IU/kg in combination with IV fluids to reduce calcium levels within the first 12 to 48 hours of treatment.

Give a bisphosphonate, eg, zoledronic acid 4 mg over 15 minutes, or pamidronate 60 to 90 mg over 2 hours. Zoledronic acid is preferred in malignancy-induced hypercal­cemia because it is more potent. Doses should be adjusted in patients with renal failure.

Give denosumab if hypercalcemia is refractory to bisphosphonates, or when bisphosphonates cannot be used in renal failure.⁹

Hemodialysis is performed in patients who have significant neurologic symptoms irrespective of acute renal insufficiency.

Our patient was started on 0.9% sodium chloride at a rate of 150 mL/h for severe hypercalcemia. Zoledronic acid 4 mg IV was given once. These measures lowered her calcium level and lessened her acute kidney injury.

ADDITIONAL FINDINGS

Urine testing was positive for Bence Jones protein. Immune electrophoresis, performed because of suspicion of multiple myeloma, showed an elevated level of kappa light chains at 806.7 mg/dL (0.33–1.94) and normal lambda light chains at 0.62 mg/dL (0.57–2.63). The immunoglobulin G level was low at 496 mg/dL (610–1,660). In patients with severe hypercalcemia, these results point to a diagnosis of malignancy. Bone marrow aspiration study showed greater than 10% plasma cells, confirming multiple myeloma.

MULTIPLE MYELOMA

The diagnosis of multiple myeloma is based in part on the presence of 10% or more of clonal bone marrow plasma cells¹⁰ and of specific end-organ damage (anemia, hypercalcemia, renal insufficiency, or bone lesions).⁹

Bone marrow clonality can be shown by the ratio of kappa to lambda light chains as  detected with immunohistochemistry, immunofluorescence, or flow cytometry.11 The normal ratio is 0.26 to 1.65 for a patient with normal kidney function. In this patient, however, the ratio was 1,301.08 (806.67 kappa to 0.62 lambda), which was extremely out of range. The patient’s bone marrow biopsy results revealed the presence of 15% clonal bone marrow plasma cells.

Multiple myeloma causes osteolytic lesions through increased activation of osteoclast activating factor that stimulates the growth of osteoclast precursors. At the same time, it inhibits osteoblast formation via multiple pathways, including the action of sclerostin.¹¹ Our patient had lytic lesions in 2 left lower ribs and in both forearms and femurs.

Hypercalcemia in multiple myeloma is attributed to 2 main factors: bone breakdown and macrophage overactivation. Multiple myeloma cells increase the release of macrophage inflammatory protein 1-alpha and tumor necrosis factor, which are inflammatory proteins that cause an increase in macrophages, which cause an increase in calcitriol.¹¹ As noted, our patient’s calcium level at presentation was 18.4 mg/dL uncorrected and 18.96 mg/dL corrected.

Cast nephropathy can occur in the distal tubules from the increased free light chains circulating and combining with Tamm-Horsfall protein, which in turn causes obstruction and local inflammation,¹² leading to a rise in creatinine levels and resulting in acute kidney injury,¹² as in our patient.

TREATMENT CONSIDERATIONS IN MULTIPLE MYELOMA

Our patient was referred to an oncologist for management.

In the management of multiple myeloma, the patient’s quality of life needs to be considered. With the development of new agents to combat the damages of the osteolytic effects, there is hope for improving quality of life.^13,14 New agents under study include anabolic agents such as antisclerostin and anti-Dickkopf-1, which promote osteoblastogenesis, leading to bone formation, with the possibility of repairing existing damage.¹⁵

TAKE-HOME POINTS

• If hypercalcemia is mild to moderate, consider primary hyperparathyroidism.
• Identify patients with severe symptoms of hypercalcemia such as volume depletion, acute kidney injury, arrhythmia, or seizures.
• Confirm severe cases of hypercalcemia and treat severe cases effectively.
• Severe hypercalcemia may need further investigation into a potential underlying malignancy.

ST. LOUIS – Getting an MRI first for suspected stroke, instead of a CT, saves money by avoiding unnecessary admissions and might lead to better outcomes, according to a review from Johns Hopkins University, Baltimore.

MRI as the first scan leads to “a definitive diagnoses sooner and helps you manage the person more rapidly and appropriately, without negatively affecting outcomes even in stroke patients who receive endovascular therapy,” said neurologist and senior investigator Argye Hillis, MD, director of the Center of Excellence in Stroke Detection and Diagnosis at Hopkins. “Consider skipping the CT and getting an MRI, and get the MRI while they are still in the emergency room.”

Almost all emergency departments in the United States are set up to get a CT first, but MRI is known to be the better study, according to the researchers. MRI is much more sensitive to stroke, especially in the first 24 hours, and pinpoints the location and extent of the damage. It can detect causes of stroke invisible to CT, with no radiation, and rule out stroke entirely, whereas CT can rule out only intracranial bleeding. Increasingly in Europe, MRI is the first study in suspected stroke, and new EDs in the United States are being designed with an in-house MRI, or one nearby.

The ED at Hopkins’ main campus in downtown Baltimore already has an MRI, and uses it first whenever possible. The problem has been that MRI techs are available only during weekdays, so physicians have to default back to CT at night and on weekends. The impetus for the review, presented at the annual meeting of the American Neurological Association, was to see if savings from unnecessary admissions prevented by MRI would be enough to offset the cost of around-the-clock staffing for the MRI scanner.

Dr. Hillis and her team reviewed 320 patients with suspected ischemic stroke who were seen at the main campus in 2018 and had CT in the ED, and then definitive diagnosis by MRI, which is the usual approach in most U.S. hospitals.

A total of 134 patients had a final diagnosis on MRI that did not justify admission; techs were available to give 75 of them MRIs in the ED after the CT, and those patients were sent home. Techs were not available, however, for 59 patients and since the CT was not able to rule out stroke, those patients were admitted. The cost of those 59 admissions was $814,016.

The cost of the noncontrast CTs for the 75 patients who were sent home after definitive MRI imaging was $28,050, plus an additional $46,072 for those who had CT neck/head angiograms. Altogether, skipping the CT and going straight to the MRI would have saved Hopkins $888,138 in 2018, enough to cover round-the-clock MRI staffing in the ED, which is now the plan at the main campus.

Once the facility moves to 24-and-7 MRI coverage, the next step in the project is to compare stroke outcomes with Johns Hopkins Bayview Medical Center, also in Baltimore, which will continue to do CT first. “We know MRI first is cheaper. We want to see if we have better outcomes. If we find they’re much better, I think many hospitals will say it’s worth the 5 minutes longer it takes to get to the MRI scanner,” Dr. Hillis said.

Stroke mimics among the 134 patients included peripheral nerve palsy and migraine, but also people simply faking it for a hot meal and a warm bed. “Its pretty common, unfortunately,” she said.

The average age for stroke admissions at Hopkins is 55 years, with as many men as women.

There was no industry funding, and Dr. Hillis didn’t have any relevant disclosures.

[email protected]

ST. LOUIS – Getting an MRI first for suspected stroke, instead of a CT, saves money by avoiding unnecessary admissions and might lead to better outcomes, according to a review from Johns Hopkins University, Baltimore.

MRI as the first scan leads to “a definitive diagnoses sooner and helps you manage the person more rapidly and appropriately, without negatively affecting outcomes even in stroke patients who receive endovascular therapy,” said neurologist and senior investigator Argye Hillis, MD, director of the Center of Excellence in Stroke Detection and Diagnosis at Hopkins. “Consider skipping the CT and getting an MRI, and get the MRI while they are still in the emergency room.”

Almost all emergency departments in the United States are set up to get a CT first, but MRI is known to be the better study, according to the researchers. MRI is much more sensitive to stroke, especially in the first 24 hours, and pinpoints the location and extent of the damage. It can detect causes of stroke invisible to CT, with no radiation, and rule out stroke entirely, whereas CT can rule out only intracranial bleeding. Increasingly in Europe, MRI is the first study in suspected stroke, and new EDs in the United States are being designed with an in-house MRI, or one nearby.

The ED at Hopkins’ main campus in downtown Baltimore already has an MRI, and uses it first whenever possible. The problem has been that MRI techs are available only during weekdays, so physicians have to default back to CT at night and on weekends. The impetus for the review, presented at the annual meeting of the American Neurological Association, was to see if savings from unnecessary admissions prevented by MRI would be enough to offset the cost of around-the-clock staffing for the MRI scanner.

Dr. Hillis and her team reviewed 320 patients with suspected ischemic stroke who were seen at the main campus in 2018 and had CT in the ED, and then definitive diagnosis by MRI, which is the usual approach in most U.S. hospitals.

A total of 134 patients had a final diagnosis on MRI that did not justify admission; techs were available to give 75 of them MRIs in the ED after the CT, and those patients were sent home. Techs were not available, however, for 59 patients and since the CT was not able to rule out stroke, those patients were admitted. The cost of those 59 admissions was $814,016.

The cost of the noncontrast CTs for the 75 patients who were sent home after definitive MRI imaging was $28,050, plus an additional $46,072 for those who had CT neck/head angiograms. Altogether, skipping the CT and going straight to the MRI would have saved Hopkins $888,138 in 2018, enough to cover round-the-clock MRI staffing in the ED, which is now the plan at the main campus.

Once the facility moves to 24-and-7 MRI coverage, the next step in the project is to compare stroke outcomes with Johns Hopkins Bayview Medical Center, also in Baltimore, which will continue to do CT first. “We know MRI first is cheaper. We want to see if we have better outcomes. If we find they’re much better, I think many hospitals will say it’s worth the 5 minutes longer it takes to get to the MRI scanner,” Dr. Hillis said.

Stroke mimics among the 134 patients included peripheral nerve palsy and migraine, but also people simply faking it for a hot meal and a warm bed. “Its pretty common, unfortunately,” she said.

The average age for stroke admissions at Hopkins is 55 years, with as many men as women.

There was no industry funding, and Dr. Hillis didn’t have any relevant disclosures.

[email protected]

ST. LOUIS – Getting an MRI first for suspected stroke, instead of a CT, saves money by avoiding unnecessary admissions and might lead to better outcomes, according to a review from Johns Hopkins University, Baltimore.

MRI as the first scan leads to “a definitive diagnoses sooner and helps you manage the person more rapidly and appropriately, without negatively affecting outcomes even in stroke patients who receive endovascular therapy,” said neurologist and senior investigator Argye Hillis, MD, director of the Center of Excellence in Stroke Detection and Diagnosis at Hopkins. “Consider skipping the CT and getting an MRI, and get the MRI while they are still in the emergency room.”

Almost all emergency departments in the United States are set up to get a CT first, but MRI is known to be the better study, according to the researchers. MRI is much more sensitive to stroke, especially in the first 24 hours, and pinpoints the location and extent of the damage. It can detect causes of stroke invisible to CT, with no radiation, and rule out stroke entirely, whereas CT can rule out only intracranial bleeding. Increasingly in Europe, MRI is the first study in suspected stroke, and new EDs in the United States are being designed with an in-house MRI, or one nearby.

The ED at Hopkins’ main campus in downtown Baltimore already has an MRI, and uses it first whenever possible. The problem has been that MRI techs are available only during weekdays, so physicians have to default back to CT at night and on weekends. The impetus for the review, presented at the annual meeting of the American Neurological Association, was to see if savings from unnecessary admissions prevented by MRI would be enough to offset the cost of around-the-clock staffing for the MRI scanner.

Dr. Hillis and her team reviewed 320 patients with suspected ischemic stroke who were seen at the main campus in 2018 and had CT in the ED, and then definitive diagnosis by MRI, which is the usual approach in most U.S. hospitals.

A total of 134 patients had a final diagnosis on MRI that did not justify admission; techs were available to give 75 of them MRIs in the ED after the CT, and those patients were sent home. Techs were not available, however, for 59 patients and since the CT was not able to rule out stroke, those patients were admitted. The cost of those 59 admissions was $814,016.

The cost of the noncontrast CTs for the 75 patients who were sent home after definitive MRI imaging was $28,050, plus an additional $46,072 for those who had CT neck/head angiograms. Altogether, skipping the CT and going straight to the MRI would have saved Hopkins $888,138 in 2018, enough to cover round-the-clock MRI staffing in the ED, which is now the plan at the main campus.

Once the facility moves to 24-and-7 MRI coverage, the next step in the project is to compare stroke outcomes with Johns Hopkins Bayview Medical Center, also in Baltimore, which will continue to do CT first. “We know MRI first is cheaper. We want to see if we have better outcomes. If we find they’re much better, I think many hospitals will say it’s worth the 5 minutes longer it takes to get to the MRI scanner,” Dr. Hillis said.

Stroke mimics among the 134 patients included peripheral nerve palsy and migraine, but also people simply faking it for a hot meal and a warm bed. “Its pretty common, unfortunately,” she said.

The average age for stroke admissions at Hopkins is 55 years, with as many men as women.

There was no industry funding, and Dr. Hillis didn’t have any relevant disclosures.

[email protected]

Autoimmune rheumatic diseases increase the risk of cardiovascular disease. In rheumatoid arthritis and systemic lupus erythematosus, the risk is driven primarily by the inflammatory milieu, leading to accelerated coronary and cerebrovascular atherosclerosis independent of traditional atherosclerotic risk factors.^1–3 The extent of cardiovascular involvement in other rheumatologic diseases has been less well characterized but is an area of growing interest.

In this review, we focus on the cardiovascular complications of systemic sclerosis and review recommendations for monitoring these patients in clinical practice.

SYSTEMIC SCLEROSIS, AN AUTOIMMUNE RHEUMATIC DISEASE

Systemic sclerosis is an autoimmune rheumatic disease characterized by excessive extracellular matrix deposition leading to diffuse fibrosis, endothelial dysfunction, and microvascular injury. It is most common in North America, Southern Europe, and Australia,^4,5 and it affects women more than men in ratios ranging from 3:1 to 14:1.⁶ The mean age at diagnosis is around 50. 

The disease can affect the lungs (interstitial lung disease and pulmonary hypertension), the heart, the kidneys, and the gastrointestinal tract.

Systemic sclerosis has 2 main subtypes: limited cutaneous systemic sclerosis, formerly called CREST syndrome) and diffuse cutaneous systemic sclerosis. The limited cutaneous subtype is characterized by tightening of the skin of the distal extremities (below the elbows and knees) and face, while diffuse cutaneous systemic sclerosis can manifest as more extensive skin tightening also involving proximal extremities and the trunk. Both subtypes can have an effect on the cardiovascular system.

Some cardiovascular risk factors such as dyslipidemia, diabetes mellitus, and high body mass index are less common in patients with systemic sclerosis than in patients with rheumatoid arthritis, while the rates of arterial hypertension, smoking, chronic obstructive pulmonary disease, osteoporosis, and neoplasms are similar between the 2 groups.⁷

HEART INVOLVEMENT HAS SERIOUS CONSEQUENCES

Overt cardiac involvement in systemic sclerosis is associated with a mortality rate of up to 70% over 5 years,^8,9 and about one-fourth of deaths in patients with systemic sclerosis are from cardiac causes.^10,11 Studies in Europe^10,12 showed that many patients with systemic sclerosis have cardiac involvement detectable by magnetic resonance imaging even if they do not have clinical disease. Pulmonary arterial hypertension (PAH) is a complication of both subtypes of systemic sclerosis and portends a higher risk of death.⁸

Thus, it is critical for clinicians to understand the potential comorbid conditions associated with systemic sclerosis, particularly the cardiovascular ones, and to work closely with cardiologists to help optimize the evaluation and management.

MECHANISMS OF CARDIAC DISEASE IN SYSTEMIC SCLEROSIS

Abnormal vasoreactivity, a consequence of an imbalance between endothelium-derived vasoconstrictors and vasodilators, defective angiogenesis, and endothelial injury, leads to tissue ischemia and vascular endothelial growth factor expression, which initiates injury and fibrosis in the myocardium and in other organs.^14–17 Fibrosis involves the myocardium, pericardium, and conduction system.^13,18

Myocardial involvement in systemic sclerosis is thought to be due mainly to abnormal vasoreactivity and microvascular abnormalities such as transient coronary artery spasm leading to repeated focal ischemia.^19,20 Abnormal vasoreactivity has been demonstrated during cardiac catheterization²¹: while mean coronary sinus blood flow in systemic sclerosis patients was normal at rest, vasodilator reserve was significantly reduced in patients with diffuse cutaneous systemic sclerosis after maximal vasodilation with dipyridamole. Additionally, endomyocardial biopsy showed fibrosis and concentric intimal hypertrophy with normal epicardial coronary arteries.²¹

More research into other mechanisms of cardiovascular disease in systemic sclerosis is needed to allow for better preventive care for these patients.

Systemic sclerosis can be associated with World Health Organization (WHO) groups 1, 2, 3, and 4 pulmonary hypertension. WHO group 1, called pulmonary arterial hypertension or PAH, is one of the most common cardiac complications of systemic sclerosis, with a reported prevalence as high as 12%.²² Systemic sclerosis-associated PAH carries a high mortality rate, with a mean survival of only 3 years.²³

With advances in treatments for other complications of systemic sclerosis, the percentage of systemic sclerosis patients who die of PAH has increased from 6% to 33%.²⁴

Compared with patients with idiopathic PAH, those with systemic sclerosis get less of a response from therapy and have poorer outcomes despite lower mean pulmonary artery pressures and similar reductions in cardiac index. However, recent studies have suggested that with aggressive treatment, patients with systemic sclerosis-related PAH can achieve outcomes similar to those with idiopathic PAH.²⁵ Thus, recognizing this condition early is imperative.

Pulmonary arterial hypertension defined

PAH is defined as the combination of all of the following²⁶:

• Mean pulmonary artery pressure > 20 mm Hg at rest
• Normal pulmonary capillary wedge pressure (≤ 15 mm Hg)
• Pulmonary vascular resistance ≥ 3 Wood units on right heart catheterization.

Other causes of pulmonary hypertension such as interstitial lung disease, chronic pulmonary thromboembolic disease, and left heart disease must be excluded.^24,27

Remodeling in the pulmonary arteries

The events that lead to PAH in systemic sclerosis remain unclear but are believed to involve initial inflammation or endothelial injury that leads to a dysequilibrium between proliferative mediators and antiproliferative vasodilators. This dysequilibrium, along with endothelial dysfunction, causes an obliterative vasculopathy in the pulmonary artery branches and arterioles. Sympathetic overactivity, hypoxemia, and ischemia-reperfusion injury additionally promote vascular proliferation, fibrosis, and remodeling, leading to increased pulmonary vascular resistance, PAH, and increased right ventricular pressures.^23,27

The subtype of systemic sclerosis is an important factor in the development and progression of PAH. PAH appears to be the major cause of death in limited cutaneous systemic sclerosis, while interstitial lung disease is the major cause of death in diffuse cutaneous systemic sclerosis.²⁸

Pulmonary arterial hypertension is a late complication of systemic sclerosis

Data from the South Australian Scleroderma Registry²⁹ revealed that PAH tends to be a late complication of systemic sclerosis, occurring around 20 years after disease onset. In this study of 608 patients, no patient with diffuse cutaneous systemic sclerosis developed PAH.

Systemic sclerosis-related PAH initially follows an indolent course with few symptoms until right ventricular function deteriorates. Early in the disease, patients may experience nonspecific symptoms of fatigue, lightheadedness, and dyspnea on exertion.²³ As it progresses, they tend to have worsening dyspnea and may experience exertional syncope, palpitations, and chest pain.

Physical findings may suggest elevated right ventricular pressure and right ventricular failure; these include a loud P2, a prominent jugular a wave, a tricuspid regurgitant murmur, jugular venous distention, and lower-extremity edema.²⁷

Screening for pulmonary arterial hypertension in systemic sclerosis

Significant signs and symptoms usually occur late in the disease; thus, it is important to appropriately screen patients who are at risk so that they can begin aggressive treatment.

Doppler echocardiography is recommended by European and American guidelines to screen for PAH in patients who have systemic sclerosis, and most agree that screening is appropriate even if the patient has no symptoms.³⁰ European consensus documents recommend that transthoracic echocardiography be done annually for the first 5 years of disease and be continued every year in patients at high risk, ie, those with anticentromere antibodies, anti-Th/To antibodies, or interstitial lung disease. Patients not at high risk of developing pulmonary hypertension should also have regular transthoracic echocardiography, though the exact timing is not defined.³¹ While American societies have not issued corresponding recommendations, many experts follow the European recommendations.

Worrisome features on echocardiography in asymptomatic patients should be followed up with right heart catheterization to assess mean right ventricular pressure. These include:

• Estimated right ventricular systolic pressure ≥ 40 mm Hg
• Tricuspid regurgitant jet velocity > 2.8 m/s
• Right atrial enlargement > 53 mm
• Right ventricular enlargement (mid-cavity dimension > 35 mm).³²

Although echocardiography is the most common form of screening, it gives only an estimate of right ventricular systolic pressure, which is imprecise. Other noninvasive markers are helpful and necessary to appropriately screen this population.

Diffusion capacity. The Itinerair study³³ found that a diffusing capacity for carbon monoxide (D_^LCO) of 60% or higher has a high specificity in excluding PAH.

Uric acid has been found to be elevated in patients with systemic sclerosis-related PAH, and levels inversely correlate with 6-minute walking distance.³⁴

Other predictors. N-terminal pro-B-type natriuretic peptide (NT-proBNP), left atrial volume, and the right ventricular myocardial performance index have also been shown to be independent predictors of PAH in patients with systemic sclerosis.³⁵

An algorithm. The DETECT study³⁶ enrolled patients at increased risk who had had systemic sclerosis longer than 3 years and a D_^LCO less than 60%. The investigators developed a 2-step algorithm to determine which patients should be referred for right heart catheterization to try to detect PAH earlier while minimizing the number of missed diagnoses and optimizing the use of invasive diagnostic right heart catheterization.

The first step was to assess serum values of anticentromere antibodies, NT-proBNP, and urate, and clinical features (telangiectasias), forced vital capacity, and electrocardiographic changes of right axis deviation to derive a prediction score. The second step was to assess surface echocardiographic features of the right atrial area and tricuspid regurgitation velocity.

This approach led to right heart catheterization in 62% of patients and was associated with a false-negative rate of 4%. Importantly, of the patients with PAH, 1 in 5 had no symptoms, and 33% had tricuspid regurgitation velocity less than 2.8 m/s. No single measurement performed well in isolation in this study.³⁷

Thus, we recommend that, in addition to routine surface echocardiography, a multimodal approach be used that includes laboratory testing, clinical features, and electrocardiographic findings when screening this high-risk patient population.

Although macrovascular disease has not typically been regarded as a significant systemic feature in systemic sclerosis, myocardial infarction and stroke are more common in patients with systemic sclerosis than in controls.^38,39

Coronary artery disease in systemic sclerosis

Man et al³⁸ reported that the incidence of myocardial infarction in patients with systemic sclerosis was 4.4 per 1,000 persons per year, and the incidence of stroke was 4.8 per 1,000 persons per year, compared with 2.5 per 1,000 persons per year for both myocardial infarction and stroke in healthy controls matched for age, sex, and time of entry.

The Australian Scleroderma Cohort Study³⁹ found a 3-fold higher prevalence of coronary artery disease in systemic sclerosis patients than in controls after factoring in traditional risk factors.

Aviña-Zubieta et al,⁴⁰ in a cohort of 1,239 systemic sclerosis patients, estimated a hazard ratio (HR) of 3.49 for myocardial infarction and 2.35 for stroke compared with age- and sex-matched controls. Not all of these events were related to macrovascular atherosclerosis—vasospasm and microvascular ischemia may have played significant roles in the etiology of clinical manifestations.

Studies of coronary atherosclerosis in systemic sclerosis are limited. An autopsy study⁴¹ of 58 patients with systemic sclerosis and 58 controls matched for age, sex, and ethnicity found that the prevalence of atherosclerosis of small coronary arteries and arterioles was significantly higher in systemic sclerosis patients than in controls (17% vs 2%, P < .01). However, the prevalence of medium-vessel coronary atherosclerosis was similar (48% vs 43%).

Why patients with systemic sclerosis develop atherosclerosis has not yet been determined. Traditional risk factors such as hypertension, dyslipidemia, diabetes mellitus, and obesity are typically no more prevalent in systemic sclerosis patients than in controls,^38,42 and thus do not explain the increased risk of atherosclerotic cardiovascular disease. There is some evidence that novel markers of atherosclerotic risk such as homocysteine,⁴³ lipoprotein[a],⁴⁴ and oxidized low-density lipoprotein⁴⁵ are more prevalent in systemic sclerosis, but these results have not been substantiated in more extensive studies.

Peripheral artery disease

It remains unclear whether peripheral artery disease is more prevalent in systemic sclerosis patients than in controls.

Individual studies have shown mixed results in comparing carotid artery stenosis between systemic sclerosis patients and controls using carotid duplex ultrasonography,⁴⁶ the ankle-brachial index,^46–48 carotid intima-media thickness,^49–54 and brachial flow-mediated dilation.^{51,53,55–58} A meta-analysis found that the carotid intima and media are significantly thicker in systemic sclerosis patients than in controls,⁵⁹ and the magnitude of difference is similar to that in other groups at increased cardiovascular risk, such as those with rheumatoid arthritis, diabetes, and familial hypercholesterolemia.^60–63

A meta-analysis of brachial artery findings showed significantly lower flow-mediated dilation in systemic sclerosis patients than in controls.⁶⁴

Overall, given the inconsistency of study results, systemic sclerosis patients should be screened and managed as in other patients with peripheral artery disease, but the clinician should be aware that there may be a higher risk of peripheral artery disease in these patients.

RIGHT AND LEFT VENTRICULAR DYSFUNCTION

Many patients with systemic sclerosis have right ventricular dysfunction as a consequence of PAH.⁶⁵ It is important to detect diastolic dysfunction in this population, as it may be an even stronger predictor of death than pulmonary hypertension on right heart catheterization (HR 3.7 vs 2.0).⁶⁶

Fewer patients have left ventricular dysfunction. In a multicenter study of 570 systemic sclerosis patients, only 1.4% had left ventricular systolic dysfunction on echocardiography, though 22.6% had left ventricular hypertrophy and 17.7% had left ventricular diastolic dysfunction.⁶⁷ In the European League Against Rheumatism (EULAR) database, the prevalence of reduced left ventricular ejection fraction was 5.4%.⁶⁸

Though traditional echocardiographic screening suggests the prevalence of left ventricular dysfunction in systemic sclerosis patients is low, cardiac magnetic resonance imaging (MRI) may be more sensitive than echocardiography for detecting subclinical myocardial involvement. Cardiac MRI has been shown to detect evidence of myocardial pathology (increased T2 signal, left ventricular thinning, pericardial effusion, reduced left ventricular and right ventricular ejection fraction, left ventricular diastolic dysfunction, and delayed myocardial contrast enhancement) in up to 75% of systemic sclerosis cases studied.⁶⁹

Patients with systemic sclerosis should already be undergoing echocardiography every year to screen for PAH, and screening should also include tissue Doppler imaging to detect various forms of left and right ventricular systolic and diastolic dysfunction that may not be clinically apparent.

Though cardiac MRI can provide useful additional information, it is not currently recommended for routine screening in patients with systemic sclerosis.

Patients with systemic sclerosis are prone to arrhythmias due to both conduction system fibrosis and myocardial damage.

Arrhythmias accounted for 6% of the deaths in the EULAR Scleroderma Trials and Research (EUSTAR) database.¹¹

In the Genetics Versus Environment in Scleroderma Outcome Study (GENISOS),⁷⁰  250 patients who had had systemic sclerosis for at least 3 years were studied during a period of approximately 6 years, during which there were 52 deaths, 29 of which were directly attributable to systemic sclerosis. Multivariable Cox modeling showed that 7 variables predicted mortality:

• Body mass index < 18.5 kg/m²
• Age ≥ 65
• Forced vital capacity < 50% predicted
• Systolic blood pressure ≥ 140 or diastolic blood pressure ≥ 90 mm Hg
• Pulmonary fibrosis
• Positive anticentromere antibodies
• Cardiac arrhythmias.

The hazard ratio for death in patients with arrhythmias in this model was 2.18 (95% CI 1.05–4.50, P = .035). Thus, finding arrhythmias in systemic sclerosis patients can provide important prognostic information.

While resting electrocardiography in patients with systemic sclerosis  most commonly shows sinus rhythm, 24-hour electrocardiographic monitoring has revealed nonsustained supraventricular and ventricular arrhythmias in a significant percentage.^71,72 Although difficult to quantify in routine practice, parameters controlled by the autonomic nervous system including heart rate variability and heart rate turbulence have been shown to be impaired in systemic sclerosis, and these measures are associated with an increased risk of malignant arrhythmias and sudden cardiac death.^73,74

Conduction abnormalities

Conduction abnormalities occur in one-fifth to one-third of patients with systemic sclerosis.^75,76 The most common abnormal conduction finding is left bundle branch block, followed by first-degree atrioventricular block. High-degree atrioventricular block is uncommon,⁷⁶ though a few case reports of complete heart block thought to be related to systemic sclerosis have been published.^77–79 An autopsy study showed that the conduction system is relatively spared from myocardial changes seen in systemic sclerosis patients, and thus it is speculated that the conduction disturbances are a consequence of damaged myocardium rather than damage to conduction tissue.⁸⁰

Given the array of electrophysiologic abnormalities that systemic sclerosis patients can have, it is critical to monitor all patients with routine (annual or biannual) electrocardiography; to take possible arrhythmia-related symptoms seriously; and to evaluate them with further workup such as Holter monitoring for 24 hours or even longer, event monitoring, exercise testing, or tilt-table testing.

PERICARDIAL DISEASE

Pericardial disease is clinically apparent in 5% to 16% of patients with systemic sclerosis⁸¹; patients with limited cutaneous systemic sclerosis have more pericardial disease than those with diffuse cutaneous systemic sclerosis (30% vs 16%).⁸² Forty-one percent of systemic sclerosis patients have been shown to have pericardial effusion by echocardiography,⁸¹ but the effusions are typically small and rarely cause tamponade, though tamponade is associated with a poor prognosis.

Large pericardial effusions can develop before skin thickening and diagnosis of systemic sclerosis.^81,83,84 Thus, systemic sclerosis should be considered in patients with pericardial effusions of unknown etiology.

In a small study,⁸⁵ the pericardial fluid in systemic sclerosis was typically exudative, with lactate dehydrogenase greater than 200 U/L, a fluid-serum lactate dehydrogenase ratio greater than 0.6, and a fluid-serum total protein ratio greater than 0.5.

Pericardial effusion can be a sign of impending scleroderma renal crisis,⁸⁶ and thus renal function should be carefully monitored in systemic sclerosis patients with pericardial effusion. Constrictive pericarditis and restrictive cardiomyopathy can rarely occur in systemic sclerosis and may more commonly present with symptoms.

Pericardial disease in systemic sclerosis should be treated in a standard fashion with nonsteroidal anti-inflammatory drugs. Corticosteroids are generally of limited benefit and should be avoided, especially in the setting of scleroderma renal crisis.⁸¹

VALVULAR HEART DISEASE

Based on limited studies, the prevalence of significant valvular heart disease in systemic sclerosis patients does not seem to be higher than that in the general population. While patients with systemic sclerosis and CREST syndrome (calcinosis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia) have been shown to have a higher frequency of mitral valve prolapse and mild mitral regurgitation,^87,88 these abnormalities do not often progress in severity, and thus their clinical significance is limited.

It is important for physicians caring for patients with systemic sclerosis to be aware of its most common cardiac manifestations, including left and right ventricular systolic and diastolic dysfunction, pulmonary hypertension, conduction abnormalities, arrhythmias, and cardiomyopathy.

Look for volume overload

On clinical examination, assess for clinical markers of volume overload such as distended neck veins, peripheral edema, or an abnormal blood pressure response to the Valsalva maneuver. These findings should prompt measurement of NT-proBNP,⁸⁹ and may warrant prescription of a diuretic.

Electrocardiography to investigate arrhythmias

Electrocardiography should be done if patients describe symptoms of palpitations, and should also include continuous rhythm monitoring with Holter or event monitoring, depending on the frequency of symptoms. Otherwise, patients should routinely undergo electrocardiography once or twice a year.

Q waves are common in systemic sclerosis patients (especially those with diffuse cutaneous systemic sclerosis), notably in the precordial leads, and can occur without coronary artery disease.⁹⁰ Symptoms such as presyncope should be further investigated with Holter monitoring and tilt-table testing.

Assess, modify traditional risk factors

Subclinical atherosclerosis as detected by carotid intima-media thickness is as common in systemic sclerosis as in rheumatoid arthritis.⁶¹ However, traditional risk indices such as SCORE (Systematic Coronary Risk Evaluation), QRISK2, and the American College of Cardiology/American Heart Association indices may underestimate risk in patients who have systemic sclerosis.

Strict hypertension control should be the goal for all systemic sclerosis patients. Though there are no specific guidelines on which antihypertensive medications are preferred, calcium channel blockers or angiotensin II receptor blockers, which are typically used to treat systemic sclerosis-related Raynaud phenomenon, may be appropriate.

Statins reduce vascular complications and are generally well tolerated in patients with systemic sclerosis.^91,92 

Aspirin is not recommended for routine primary prevention in view of data suggesting that its benefits in diabetic patients are counterbalanced by increased bleeding risk.⁹³

Echocardiography to detect pulmonary arterial hypertension

At this time, guidelines for monitoring for cardiovascular manifestations in systemic sclerosis patients are limited. The only well-defined ones are European consensus guidelines, which suggest annual transthoracic echocardiography for the first 5 years after systemic sclerosis is diagnosed and continued annual screening in patients at risk of developing PAH.³¹

We support this strategy, with annual screening for the first 5 years followed by surveillance echocardiography every 2 to 3 years unless there is a high risk of PAH. Specific attention should be paid to right ventricular diastolic function, right atrial volume, and right ventricular myocardial performance index.

Emerging data suggest that the addition of global longitudinal strain of ventricles to  routine echocardiography can help detect subclinical cardiac risk.⁹⁴ Although further study is needed into the predictive value of global longitudinal strain, it is a low-cost and noninvasive addition to standard echocardiography that can help guide risk stratification, and thus we recommend that it be part of the echocardiographic examination for all systemic sclerosis patients.

Pulmonary function testing. In addition to screening for PAH with echocardiography, we recommend obtaining baseline pulmonary function tests, including D_^LCO, at the time systemic sclerosis is diagnosed, with repeat testing annually.

Magnetic resonance imaging

While echocardiography is the gold standard for monitoring systemic sclerosis patients, cardiovascular MRI may have a role in identifying those at higher risk of dangerous arrhythmias such as ventricular tachycardia and ventricular fibrillation. In addition to assessing ventricular function, MRI can detect myocardial inflammation, ischemia, and fibrosis that may predispose a patient to develop ventricular tachycardia or fibrillation.⁹⁵ Variables such as T1/T2 mapping, extracellular volume fraction, T2 signal ratio, and early vs late gadolinium enhancement can help identify patients who had past ventricular tachycardia or fibrillation.⁹⁶

Finding an increased risk of arrhythmias may prompt a conversation between the patient and the physician about the need for an implantable cardiac defibrillator.

If cardiac MRI is available and is reimbursed by the patient’s insurance carrier, physicians should strongly consider obtaining at least one baseline scan in systemic sclerosis patients to identify those at risk of highly fatal arrhythmias.

Teamwork is needed

Systemic sclerosis has not traditionally been associated with cardiovascular disease to the extent of other rheumatic conditions, but the cardiovascular system can be affected in various ways that can ultimately lead to an early death. These manifestations may be asymptomatic for long periods, and overt clinical disease portends a poorer prognosis.

Primary care physicians managing these patients should be aware of the cardiovascular complications of systemic sclerosis and should implement appropriate screening tests in conjunction with rheumatologists and cardiologists. It is also essential for general and subspecialty cardiologists to understand the broad spectrum of organ system involvement that can affect systemic sclerosis patients and to tailor their investigation and management recommendations accordingly. By designing a multidisciplinary approach to the treatment of systemic sclerosis patients, physicians can help to optimize cardiovascular risk modification in this vulnerable population.

Autoimmune rheumatic diseases increase the risk of cardiovascular disease. In rheumatoid arthritis and systemic lupus erythematosus, the risk is driven primarily by the inflammatory milieu, leading to accelerated coronary and cerebrovascular atherosclerosis independent of traditional atherosclerotic risk factors.^1–3 The extent of cardiovascular involvement in other rheumatologic diseases has been less well characterized but is an area of growing interest.

In this review, we focus on the cardiovascular complications of systemic sclerosis and review recommendations for monitoring these patients in clinical practice.

SYSTEMIC SCLEROSIS, AN AUTOIMMUNE RHEUMATIC DISEASE

Systemic sclerosis is an autoimmune rheumatic disease characterized by excessive extracellular matrix deposition leading to diffuse fibrosis, endothelial dysfunction, and microvascular injury. It is most common in North America, Southern Europe, and Australia,^4,5 and it affects women more than men in ratios ranging from 3:1 to 14:1.⁶ The mean age at diagnosis is around 50. 

The disease can affect the lungs (interstitial lung disease and pulmonary hypertension), the heart, the kidneys, and the gastrointestinal tract.

Systemic sclerosis has 2 main subtypes: limited cutaneous systemic sclerosis, formerly called CREST syndrome) and diffuse cutaneous systemic sclerosis. The limited cutaneous subtype is characterized by tightening of the skin of the distal extremities (below the elbows and knees) and face, while diffuse cutaneous systemic sclerosis can manifest as more extensive skin tightening also involving proximal extremities and the trunk. Both subtypes can have an effect on the cardiovascular system.

Some cardiovascular risk factors such as dyslipidemia, diabetes mellitus, and high body mass index are less common in patients with systemic sclerosis than in patients with rheumatoid arthritis, while the rates of arterial hypertension, smoking, chronic obstructive pulmonary disease, osteoporosis, and neoplasms are similar between the 2 groups.⁷

HEART INVOLVEMENT HAS SERIOUS CONSEQUENCES

Overt cardiac involvement in systemic sclerosis is associated with a mortality rate of up to 70% over 5 years,^8,9 and about one-fourth of deaths in patients with systemic sclerosis are from cardiac causes.^10,11 Studies in Europe^10,12 showed that many patients with systemic sclerosis have cardiac involvement detectable by magnetic resonance imaging even if they do not have clinical disease. Pulmonary arterial hypertension (PAH) is a complication of both subtypes of systemic sclerosis and portends a higher risk of death.⁸

Thus, it is critical for clinicians to understand the potential comorbid conditions associated with systemic sclerosis, particularly the cardiovascular ones, and to work closely with cardiologists to help optimize the evaluation and management.

MECHANISMS OF CARDIAC DISEASE IN SYSTEMIC SCLEROSIS

Abnormal vasoreactivity, a consequence of an imbalance between endothelium-derived vasoconstrictors and vasodilators, defective angiogenesis, and endothelial injury, leads to tissue ischemia and vascular endothelial growth factor expression, which initiates injury and fibrosis in the myocardium and in other organs.^14–17 Fibrosis involves the myocardium, pericardium, and conduction system.^13,18

Myocardial involvement in systemic sclerosis is thought to be due mainly to abnormal vasoreactivity and microvascular abnormalities such as transient coronary artery spasm leading to repeated focal ischemia.^19,20 Abnormal vasoreactivity has been demonstrated during cardiac catheterization²¹: while mean coronary sinus blood flow in systemic sclerosis patients was normal at rest, vasodilator reserve was significantly reduced in patients with diffuse cutaneous systemic sclerosis after maximal vasodilation with dipyridamole. Additionally, endomyocardial biopsy showed fibrosis and concentric intimal hypertrophy with normal epicardial coronary arteries.²¹

More research into other mechanisms of cardiovascular disease in systemic sclerosis is needed to allow for better preventive care for these patients.

Systemic sclerosis can be associated with World Health Organization (WHO) groups 1, 2, 3, and 4 pulmonary hypertension. WHO group 1, called pulmonary arterial hypertension or PAH, is one of the most common cardiac complications of systemic sclerosis, with a reported prevalence as high as 12%.²² Systemic sclerosis-associated PAH carries a high mortality rate, with a mean survival of only 3 years.²³

With advances in treatments for other complications of systemic sclerosis, the percentage of systemic sclerosis patients who die of PAH has increased from 6% to 33%.²⁴

Compared with patients with idiopathic PAH, those with systemic sclerosis get less of a response from therapy and have poorer outcomes despite lower mean pulmonary artery pressures and similar reductions in cardiac index. However, recent studies have suggested that with aggressive treatment, patients with systemic sclerosis-related PAH can achieve outcomes similar to those with idiopathic PAH.²⁵ Thus, recognizing this condition early is imperative.

Pulmonary arterial hypertension defined

PAH is defined as the combination of all of the following²⁶:

• Mean pulmonary artery pressure > 20 mm Hg at rest
• Normal pulmonary capillary wedge pressure (≤ 15 mm Hg)
• Pulmonary vascular resistance ≥ 3 Wood units on right heart catheterization.

Other causes of pulmonary hypertension such as interstitial lung disease, chronic pulmonary thromboembolic disease, and left heart disease must be excluded.^24,27

Remodeling in the pulmonary arteries

The events that lead to PAH in systemic sclerosis remain unclear but are believed to involve initial inflammation or endothelial injury that leads to a dysequilibrium between proliferative mediators and antiproliferative vasodilators. This dysequilibrium, along with endothelial dysfunction, causes an obliterative vasculopathy in the pulmonary artery branches and arterioles. Sympathetic overactivity, hypoxemia, and ischemia-reperfusion injury additionally promote vascular proliferation, fibrosis, and remodeling, leading to increased pulmonary vascular resistance, PAH, and increased right ventricular pressures.^23,27

The subtype of systemic sclerosis is an important factor in the development and progression of PAH. PAH appears to be the major cause of death in limited cutaneous systemic sclerosis, while interstitial lung disease is the major cause of death in diffuse cutaneous systemic sclerosis.²⁸

Pulmonary arterial hypertension is a late complication of systemic sclerosis

Data from the South Australian Scleroderma Registry²⁹ revealed that PAH tends to be a late complication of systemic sclerosis, occurring around 20 years after disease onset. In this study of 608 patients, no patient with diffuse cutaneous systemic sclerosis developed PAH.

Systemic sclerosis-related PAH initially follows an indolent course with few symptoms until right ventricular function deteriorates. Early in the disease, patients may experience nonspecific symptoms of fatigue, lightheadedness, and dyspnea on exertion.²³ As it progresses, they tend to have worsening dyspnea and may experience exertional syncope, palpitations, and chest pain.

Physical findings may suggest elevated right ventricular pressure and right ventricular failure; these include a loud P2, a prominent jugular a wave, a tricuspid regurgitant murmur, jugular venous distention, and lower-extremity edema.²⁷

Screening for pulmonary arterial hypertension in systemic sclerosis

Significant signs and symptoms usually occur late in the disease; thus, it is important to appropriately screen patients who are at risk so that they can begin aggressive treatment.

Doppler echocardiography is recommended by European and American guidelines to screen for PAH in patients who have systemic sclerosis, and most agree that screening is appropriate even if the patient has no symptoms.³⁰ European consensus documents recommend that transthoracic echocardiography be done annually for the first 5 years of disease and be continued every year in patients at high risk, ie, those with anticentromere antibodies, anti-Th/To antibodies, or interstitial lung disease. Patients not at high risk of developing pulmonary hypertension should also have regular transthoracic echocardiography, though the exact timing is not defined.³¹ While American societies have not issued corresponding recommendations, many experts follow the European recommendations.

Worrisome features on echocardiography in asymptomatic patients should be followed up with right heart catheterization to assess mean right ventricular pressure. These include:

• Estimated right ventricular systolic pressure ≥ 40 mm Hg
• Tricuspid regurgitant jet velocity > 2.8 m/s
• Right atrial enlargement > 53 mm
• Right ventricular enlargement (mid-cavity dimension > 35 mm).³²

Although echocardiography is the most common form of screening, it gives only an estimate of right ventricular systolic pressure, which is imprecise. Other noninvasive markers are helpful and necessary to appropriately screen this population.

Diffusion capacity. The Itinerair study³³ found that a diffusing capacity for carbon monoxide (D_^LCO) of 60% or higher has a high specificity in excluding PAH.

Uric acid has been found to be elevated in patients with systemic sclerosis-related PAH, and levels inversely correlate with 6-minute walking distance.³⁴

Other predictors. N-terminal pro-B-type natriuretic peptide (NT-proBNP), left atrial volume, and the right ventricular myocardial performance index have also been shown to be independent predictors of PAH in patients with systemic sclerosis.³⁵

An algorithm. The DETECT study³⁶ enrolled patients at increased risk who had had systemic sclerosis longer than 3 years and a D_^LCO less than 60%. The investigators developed a 2-step algorithm to determine which patients should be referred for right heart catheterization to try to detect PAH earlier while minimizing the number of missed diagnoses and optimizing the use of invasive diagnostic right heart catheterization.

The first step was to assess serum values of anticentromere antibodies, NT-proBNP, and urate, and clinical features (telangiectasias), forced vital capacity, and electrocardiographic changes of right axis deviation to derive a prediction score. The second step was to assess surface echocardiographic features of the right atrial area and tricuspid regurgitation velocity.

This approach led to right heart catheterization in 62% of patients and was associated with a false-negative rate of 4%. Importantly, of the patients with PAH, 1 in 5 had no symptoms, and 33% had tricuspid regurgitation velocity less than 2.8 m/s. No single measurement performed well in isolation in this study.³⁷

Thus, we recommend that, in addition to routine surface echocardiography, a multimodal approach be used that includes laboratory testing, clinical features, and electrocardiographic findings when screening this high-risk patient population.

Although macrovascular disease has not typically been regarded as a significant systemic feature in systemic sclerosis, myocardial infarction and stroke are more common in patients with systemic sclerosis than in controls.^38,39

Coronary artery disease in systemic sclerosis

Man et al³⁸ reported that the incidence of myocardial infarction in patients with systemic sclerosis was 4.4 per 1,000 persons per year, and the incidence of stroke was 4.8 per 1,000 persons per year, compared with 2.5 per 1,000 persons per year for both myocardial infarction and stroke in healthy controls matched for age, sex, and time of entry.

The Australian Scleroderma Cohort Study³⁹ found a 3-fold higher prevalence of coronary artery disease in systemic sclerosis patients than in controls after factoring in traditional risk factors.

Aviña-Zubieta et al,⁴⁰ in a cohort of 1,239 systemic sclerosis patients, estimated a hazard ratio (HR) of 3.49 for myocardial infarction and 2.35 for stroke compared with age- and sex-matched controls. Not all of these events were related to macrovascular atherosclerosis—vasospasm and microvascular ischemia may have played significant roles in the etiology of clinical manifestations.

Studies of coronary atherosclerosis in systemic sclerosis are limited. An autopsy study⁴¹ of 58 patients with systemic sclerosis and 58 controls matched for age, sex, and ethnicity found that the prevalence of atherosclerosis of small coronary arteries and arterioles was significantly higher in systemic sclerosis patients than in controls (17% vs 2%, P < .01). However, the prevalence of medium-vessel coronary atherosclerosis was similar (48% vs 43%).

Why patients with systemic sclerosis develop atherosclerosis has not yet been determined. Traditional risk factors such as hypertension, dyslipidemia, diabetes mellitus, and obesity are typically no more prevalent in systemic sclerosis patients than in controls,^38,42 and thus do not explain the increased risk of atherosclerotic cardiovascular disease. There is some evidence that novel markers of atherosclerotic risk such as homocysteine,⁴³ lipoprotein[a],⁴⁴ and oxidized low-density lipoprotein⁴⁵ are more prevalent in systemic sclerosis, but these results have not been substantiated in more extensive studies.

Peripheral artery disease

It remains unclear whether peripheral artery disease is more prevalent in systemic sclerosis patients than in controls.

Individual studies have shown mixed results in comparing carotid artery stenosis between systemic sclerosis patients and controls using carotid duplex ultrasonography,⁴⁶ the ankle-brachial index,^46–48 carotid intima-media thickness,^49–54 and brachial flow-mediated dilation.^{51,53,55–58} A meta-analysis found that the carotid intima and media are significantly thicker in systemic sclerosis patients than in controls,⁵⁹ and the magnitude of difference is similar to that in other groups at increased cardiovascular risk, such as those with rheumatoid arthritis, diabetes, and familial hypercholesterolemia.^60–63

A meta-analysis of brachial artery findings showed significantly lower flow-mediated dilation in systemic sclerosis patients than in controls.⁶⁴

Overall, given the inconsistency of study results, systemic sclerosis patients should be screened and managed as in other patients with peripheral artery disease, but the clinician should be aware that there may be a higher risk of peripheral artery disease in these patients.

RIGHT AND LEFT VENTRICULAR DYSFUNCTION

Many patients with systemic sclerosis have right ventricular dysfunction as a consequence of PAH.⁶⁵ It is important to detect diastolic dysfunction in this population, as it may be an even stronger predictor of death than pulmonary hypertension on right heart catheterization (HR 3.7 vs 2.0).⁶⁶

Fewer patients have left ventricular dysfunction. In a multicenter study of 570 systemic sclerosis patients, only 1.4% had left ventricular systolic dysfunction on echocardiography, though 22.6% had left ventricular hypertrophy and 17.7% had left ventricular diastolic dysfunction.⁶⁷ In the European League Against Rheumatism (EULAR) database, the prevalence of reduced left ventricular ejection fraction was 5.4%.⁶⁸

Though traditional echocardiographic screening suggests the prevalence of left ventricular dysfunction in systemic sclerosis patients is low, cardiac magnetic resonance imaging (MRI) may be more sensitive than echocardiography for detecting subclinical myocardial involvement. Cardiac MRI has been shown to detect evidence of myocardial pathology (increased T2 signal, left ventricular thinning, pericardial effusion, reduced left ventricular and right ventricular ejection fraction, left ventricular diastolic dysfunction, and delayed myocardial contrast enhancement) in up to 75% of systemic sclerosis cases studied.⁶⁹

Patients with systemic sclerosis should already be undergoing echocardiography every year to screen for PAH, and screening should also include tissue Doppler imaging to detect various forms of left and right ventricular systolic and diastolic dysfunction that may not be clinically apparent.

Though cardiac MRI can provide useful additional information, it is not currently recommended for routine screening in patients with systemic sclerosis.

Patients with systemic sclerosis are prone to arrhythmias due to both conduction system fibrosis and myocardial damage.

Arrhythmias accounted for 6% of the deaths in the EULAR Scleroderma Trials and Research (EUSTAR) database.¹¹

In the Genetics Versus Environment in Scleroderma Outcome Study (GENISOS),⁷⁰  250 patients who had had systemic sclerosis for at least 3 years were studied during a period of approximately 6 years, during which there were 52 deaths, 29 of which were directly attributable to systemic sclerosis. Multivariable Cox modeling showed that 7 variables predicted mortality:

• Body mass index < 18.5 kg/m²
• Age ≥ 65
• Forced vital capacity < 50% predicted
• Systolic blood pressure ≥ 140 or diastolic blood pressure ≥ 90 mm Hg
• Pulmonary fibrosis
• Positive anticentromere antibodies
• Cardiac arrhythmias.

The hazard ratio for death in patients with arrhythmias in this model was 2.18 (95% CI 1.05–4.50, P = .035). Thus, finding arrhythmias in systemic sclerosis patients can provide important prognostic information.

While resting electrocardiography in patients with systemic sclerosis  most commonly shows sinus rhythm, 24-hour electrocardiographic monitoring has revealed nonsustained supraventricular and ventricular arrhythmias in a significant percentage.^71,72 Although difficult to quantify in routine practice, parameters controlled by the autonomic nervous system including heart rate variability and heart rate turbulence have been shown to be impaired in systemic sclerosis, and these measures are associated with an increased risk of malignant arrhythmias and sudden cardiac death.^73,74

Conduction abnormalities

Conduction abnormalities occur in one-fifth to one-third of patients with systemic sclerosis.^75,76 The most common abnormal conduction finding is left bundle branch block, followed by first-degree atrioventricular block. High-degree atrioventricular block is uncommon,⁷⁶ though a few case reports of complete heart block thought to be related to systemic sclerosis have been published.^77–79 An autopsy study showed that the conduction system is relatively spared from myocardial changes seen in systemic sclerosis patients, and thus it is speculated that the conduction disturbances are a consequence of damaged myocardium rather than damage to conduction tissue.⁸⁰

Given the array of electrophysiologic abnormalities that systemic sclerosis patients can have, it is critical to monitor all patients with routine (annual or biannual) electrocardiography; to take possible arrhythmia-related symptoms seriously; and to evaluate them with further workup such as Holter monitoring for 24 hours or even longer, event monitoring, exercise testing, or tilt-table testing.

PERICARDIAL DISEASE

Pericardial disease is clinically apparent in 5% to 16% of patients with systemic sclerosis⁸¹; patients with limited cutaneous systemic sclerosis have more pericardial disease than those with diffuse cutaneous systemic sclerosis (30% vs 16%).⁸² Forty-one percent of systemic sclerosis patients have been shown to have pericardial effusion by echocardiography,⁸¹ but the effusions are typically small and rarely cause tamponade, though tamponade is associated with a poor prognosis.

Large pericardial effusions can develop before skin thickening and diagnosis of systemic sclerosis.^81,83,84 Thus, systemic sclerosis should be considered in patients with pericardial effusions of unknown etiology.

In a small study,⁸⁵ the pericardial fluid in systemic sclerosis was typically exudative, with lactate dehydrogenase greater than 200 U/L, a fluid-serum lactate dehydrogenase ratio greater than 0.6, and a fluid-serum total protein ratio greater than 0.5.

Pericardial effusion can be a sign of impending scleroderma renal crisis,⁸⁶ and thus renal function should be carefully monitored in systemic sclerosis patients with pericardial effusion. Constrictive pericarditis and restrictive cardiomyopathy can rarely occur in systemic sclerosis and may more commonly present with symptoms.

Pericardial disease in systemic sclerosis should be treated in a standard fashion with nonsteroidal anti-inflammatory drugs. Corticosteroids are generally of limited benefit and should be avoided, especially in the setting of scleroderma renal crisis.⁸¹

VALVULAR HEART DISEASE

Based on limited studies, the prevalence of significant valvular heart disease in systemic sclerosis patients does not seem to be higher than that in the general population. While patients with systemic sclerosis and CREST syndrome (calcinosis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia) have been shown to have a higher frequency of mitral valve prolapse and mild mitral regurgitation,^87,88 these abnormalities do not often progress in severity, and thus their clinical significance is limited.

It is important for physicians caring for patients with systemic sclerosis to be aware of its most common cardiac manifestations, including left and right ventricular systolic and diastolic dysfunction, pulmonary hypertension, conduction abnormalities, arrhythmias, and cardiomyopathy.

Look for volume overload

On clinical examination, assess for clinical markers of volume overload such as distended neck veins, peripheral edema, or an abnormal blood pressure response to the Valsalva maneuver. These findings should prompt measurement of NT-proBNP,⁸⁹ and may warrant prescription of a diuretic.

Electrocardiography to investigate arrhythmias

Electrocardiography should be done if patients describe symptoms of palpitations, and should also include continuous rhythm monitoring with Holter or event monitoring, depending on the frequency of symptoms. Otherwise, patients should routinely undergo electrocardiography once or twice a year.

Q waves are common in systemic sclerosis patients (especially those with diffuse cutaneous systemic sclerosis), notably in the precordial leads, and can occur without coronary artery disease.⁹⁰ Symptoms such as presyncope should be further investigated with Holter monitoring and tilt-table testing.

Assess, modify traditional risk factors

Subclinical atherosclerosis as detected by carotid intima-media thickness is as common in systemic sclerosis as in rheumatoid arthritis.⁶¹ However, traditional risk indices such as SCORE (Systematic Coronary Risk Evaluation), QRISK2, and the American College of Cardiology/American Heart Association indices may underestimate risk in patients who have systemic sclerosis.

Strict hypertension control should be the goal for all systemic sclerosis patients. Though there are no specific guidelines on which antihypertensive medications are preferred, calcium channel blockers or angiotensin II receptor blockers, which are typically used to treat systemic sclerosis-related Raynaud phenomenon, may be appropriate.

Statins reduce vascular complications and are generally well tolerated in patients with systemic sclerosis.^91,92 

Aspirin is not recommended for routine primary prevention in view of data suggesting that its benefits in diabetic patients are counterbalanced by increased bleeding risk.⁹³

Echocardiography to detect pulmonary arterial hypertension

At this time, guidelines for monitoring for cardiovascular manifestations in systemic sclerosis patients are limited. The only well-defined ones are European consensus guidelines, which suggest annual transthoracic echocardiography for the first 5 years after systemic sclerosis is diagnosed and continued annual screening in patients at risk of developing PAH.³¹

We support this strategy, with annual screening for the first 5 years followed by surveillance echocardiography every 2 to 3 years unless there is a high risk of PAH. Specific attention should be paid to right ventricular diastolic function, right atrial volume, and right ventricular myocardial performance index.

Emerging data suggest that the addition of global longitudinal strain of ventricles to  routine echocardiography can help detect subclinical cardiac risk.⁹⁴ Although further study is needed into the predictive value of global longitudinal strain, it is a low-cost and noninvasive addition to standard echocardiography that can help guide risk stratification, and thus we recommend that it be part of the echocardiographic examination for all systemic sclerosis patients.

Pulmonary function testing. In addition to screening for PAH with echocardiography, we recommend obtaining baseline pulmonary function tests, including D_^LCO, at the time systemic sclerosis is diagnosed, with repeat testing annually.

Magnetic resonance imaging

While echocardiography is the gold standard for monitoring systemic sclerosis patients, cardiovascular MRI may have a role in identifying those at higher risk of dangerous arrhythmias such as ventricular tachycardia and ventricular fibrillation. In addition to assessing ventricular function, MRI can detect myocardial inflammation, ischemia, and fibrosis that may predispose a patient to develop ventricular tachycardia or fibrillation.⁹⁵ Variables such as T1/T2 mapping, extracellular volume fraction, T2 signal ratio, and early vs late gadolinium enhancement can help identify patients who had past ventricular tachycardia or fibrillation.⁹⁶

Finding an increased risk of arrhythmias may prompt a conversation between the patient and the physician about the need for an implantable cardiac defibrillator.

If cardiac MRI is available and is reimbursed by the patient’s insurance carrier, physicians should strongly consider obtaining at least one baseline scan in systemic sclerosis patients to identify those at risk of highly fatal arrhythmias.

Teamwork is needed

Systemic sclerosis has not traditionally been associated with cardiovascular disease to the extent of other rheumatic conditions, but the cardiovascular system can be affected in various ways that can ultimately lead to an early death. These manifestations may be asymptomatic for long periods, and overt clinical disease portends a poorer prognosis.

Primary care physicians managing these patients should be aware of the cardiovascular complications of systemic sclerosis and should implement appropriate screening tests in conjunction with rheumatologists and cardiologists. It is also essential for general and subspecialty cardiologists to understand the broad spectrum of organ system involvement that can affect systemic sclerosis patients and to tailor their investigation and management recommendations accordingly. By designing a multidisciplinary approach to the treatment of systemic sclerosis patients, physicians can help to optimize cardiovascular risk modification in this vulnerable population.

Autoimmune rheumatic diseases increase the risk of cardiovascular disease. In rheumatoid arthritis and systemic lupus erythematosus, the risk is driven primarily by the inflammatory milieu, leading to accelerated coronary and cerebrovascular atherosclerosis independent of traditional atherosclerotic risk factors.^1–3 The extent of cardiovascular involvement in other rheumatologic diseases has been less well characterized but is an area of growing interest.

In this review, we focus on the cardiovascular complications of systemic sclerosis and review recommendations for monitoring these patients in clinical practice.

SYSTEMIC SCLEROSIS, AN AUTOIMMUNE RHEUMATIC DISEASE

Systemic sclerosis is an autoimmune rheumatic disease characterized by excessive extracellular matrix deposition leading to diffuse fibrosis, endothelial dysfunction, and microvascular injury. It is most common in North America, Southern Europe, and Australia,^4,5 and it affects women more than men in ratios ranging from 3:1 to 14:1.⁶ The mean age at diagnosis is around 50. 

The disease can affect the lungs (interstitial lung disease and pulmonary hypertension), the heart, the kidneys, and the gastrointestinal tract.

Systemic sclerosis has 2 main subtypes: limited cutaneous systemic sclerosis, formerly called CREST syndrome) and diffuse cutaneous systemic sclerosis. The limited cutaneous subtype is characterized by tightening of the skin of the distal extremities (below the elbows and knees) and face, while diffuse cutaneous systemic sclerosis can manifest as more extensive skin tightening also involving proximal extremities and the trunk. Both subtypes can have an effect on the cardiovascular system.

Some cardiovascular risk factors such as dyslipidemia, diabetes mellitus, and high body mass index are less common in patients with systemic sclerosis than in patients with rheumatoid arthritis, while the rates of arterial hypertension, smoking, chronic obstructive pulmonary disease, osteoporosis, and neoplasms are similar between the 2 groups.⁷

HEART INVOLVEMENT HAS SERIOUS CONSEQUENCES

Overt cardiac involvement in systemic sclerosis is associated with a mortality rate of up to 70% over 5 years,^8,9 and about one-fourth of deaths in patients with systemic sclerosis are from cardiac causes.^10,11 Studies in Europe^10,12 showed that many patients with systemic sclerosis have cardiac involvement detectable by magnetic resonance imaging even if they do not have clinical disease. Pulmonary arterial hypertension (PAH) is a complication of both subtypes of systemic sclerosis and portends a higher risk of death.⁸

Thus, it is critical for clinicians to understand the potential comorbid conditions associated with systemic sclerosis, particularly the cardiovascular ones, and to work closely with cardiologists to help optimize the evaluation and management.

MECHANISMS OF CARDIAC DISEASE IN SYSTEMIC SCLEROSIS

Abnormal vasoreactivity, a consequence of an imbalance between endothelium-derived vasoconstrictors and vasodilators, defective angiogenesis, and endothelial injury, leads to tissue ischemia and vascular endothelial growth factor expression, which initiates injury and fibrosis in the myocardium and in other organs.^14–17 Fibrosis involves the myocardium, pericardium, and conduction system.^13,18

Myocardial involvement in systemic sclerosis is thought to be due mainly to abnormal vasoreactivity and microvascular abnormalities such as transient coronary artery spasm leading to repeated focal ischemia.^19,20 Abnormal vasoreactivity has been demonstrated during cardiac catheterization²¹: while mean coronary sinus blood flow in systemic sclerosis patients was normal at rest, vasodilator reserve was significantly reduced in patients with diffuse cutaneous systemic sclerosis after maximal vasodilation with dipyridamole. Additionally, endomyocardial biopsy showed fibrosis and concentric intimal hypertrophy with normal epicardial coronary arteries.²¹

More research into other mechanisms of cardiovascular disease in systemic sclerosis is needed to allow for better preventive care for these patients.

Systemic sclerosis can be associated with World Health Organization (WHO) groups 1, 2, 3, and 4 pulmonary hypertension. WHO group 1, called pulmonary arterial hypertension or PAH, is one of the most common cardiac complications of systemic sclerosis, with a reported prevalence as high as 12%.²² Systemic sclerosis-associated PAH carries a high mortality rate, with a mean survival of only 3 years.²³

With advances in treatments for other complications of systemic sclerosis, the percentage of systemic sclerosis patients who die of PAH has increased from 6% to 33%.²⁴

Compared with patients with idiopathic PAH, those with systemic sclerosis get less of a response from therapy and have poorer outcomes despite lower mean pulmonary artery pressures and similar reductions in cardiac index. However, recent studies have suggested that with aggressive treatment, patients with systemic sclerosis-related PAH can achieve outcomes similar to those with idiopathic PAH.²⁵ Thus, recognizing this condition early is imperative.

Pulmonary arterial hypertension defined

PAH is defined as the combination of all of the following²⁶:

• Mean pulmonary artery pressure > 20 mm Hg at rest
• Normal pulmonary capillary wedge pressure (≤ 15 mm Hg)
• Pulmonary vascular resistance ≥ 3 Wood units on right heart catheterization.

Other causes of pulmonary hypertension such as interstitial lung disease, chronic pulmonary thromboembolic disease, and left heart disease must be excluded.^24,27

Remodeling in the pulmonary arteries

The events that lead to PAH in systemic sclerosis remain unclear but are believed to involve initial inflammation or endothelial injury that leads to a dysequilibrium between proliferative mediators and antiproliferative vasodilators. This dysequilibrium, along with endothelial dysfunction, causes an obliterative vasculopathy in the pulmonary artery branches and arterioles. Sympathetic overactivity, hypoxemia, and ischemia-reperfusion injury additionally promote vascular proliferation, fibrosis, and remodeling, leading to increased pulmonary vascular resistance, PAH, and increased right ventricular pressures.^23,27

The subtype of systemic sclerosis is an important factor in the development and progression of PAH. PAH appears to be the major cause of death in limited cutaneous systemic sclerosis, while interstitial lung disease is the major cause of death in diffuse cutaneous systemic sclerosis.²⁸

Pulmonary arterial hypertension is a late complication of systemic sclerosis

Data from the South Australian Scleroderma Registry²⁹ revealed that PAH tends to be a late complication of systemic sclerosis, occurring around 20 years after disease onset. In this study of 608 patients, no patient with diffuse cutaneous systemic sclerosis developed PAH.

Systemic sclerosis-related PAH initially follows an indolent course with few symptoms until right ventricular function deteriorates. Early in the disease, patients may experience nonspecific symptoms of fatigue, lightheadedness, and dyspnea on exertion.²³ As it progresses, they tend to have worsening dyspnea and may experience exertional syncope, palpitations, and chest pain.

Physical findings may suggest elevated right ventricular pressure and right ventricular failure; these include a loud P2, a prominent jugular a wave, a tricuspid regurgitant murmur, jugular venous distention, and lower-extremity edema.²⁷

Screening for pulmonary arterial hypertension in systemic sclerosis

Significant signs and symptoms usually occur late in the disease; thus, it is important to appropriately screen patients who are at risk so that they can begin aggressive treatment.

Doppler echocardiography is recommended by European and American guidelines to screen for PAH in patients who have systemic sclerosis, and most agree that screening is appropriate even if the patient has no symptoms.³⁰ European consensus documents recommend that transthoracic echocardiography be done annually for the first 5 years of disease and be continued every year in patients at high risk, ie, those with anticentromere antibodies, anti-Th/To antibodies, or interstitial lung disease. Patients not at high risk of developing pulmonary hypertension should also have regular transthoracic echocardiography, though the exact timing is not defined.³¹ While American societies have not issued corresponding recommendations, many experts follow the European recommendations.

Worrisome features on echocardiography in asymptomatic patients should be followed up with right heart catheterization to assess mean right ventricular pressure. These include:

• Estimated right ventricular systolic pressure ≥ 40 mm Hg
• Tricuspid regurgitant jet velocity > 2.8 m/s
• Right atrial enlargement > 53 mm
• Right ventricular enlargement (mid-cavity dimension > 35 mm).³²

Although echocardiography is the most common form of screening, it gives only an estimate of right ventricular systolic pressure, which is imprecise. Other noninvasive markers are helpful and necessary to appropriately screen this population.

Diffusion capacity. The Itinerair study³³ found that a diffusing capacity for carbon monoxide (D_^LCO) of 60% or higher has a high specificity in excluding PAH.

Uric acid has been found to be elevated in patients with systemic sclerosis-related PAH, and levels inversely correlate with 6-minute walking distance.³⁴

Other predictors. N-terminal pro-B-type natriuretic peptide (NT-proBNP), left atrial volume, and the right ventricular myocardial performance index have also been shown to be independent predictors of PAH in patients with systemic sclerosis.³⁵

An algorithm. The DETECT study³⁶ enrolled patients at increased risk who had had systemic sclerosis longer than 3 years and a D_^LCO less than 60%. The investigators developed a 2-step algorithm to determine which patients should be referred for right heart catheterization to try to detect PAH earlier while minimizing the number of missed diagnoses and optimizing the use of invasive diagnostic right heart catheterization.

The first step was to assess serum values of anticentromere antibodies, NT-proBNP, and urate, and clinical features (telangiectasias), forced vital capacity, and electrocardiographic changes of right axis deviation to derive a prediction score. The second step was to assess surface echocardiographic features of the right atrial area and tricuspid regurgitation velocity.

This approach led to right heart catheterization in 62% of patients and was associated with a false-negative rate of 4%. Importantly, of the patients with PAH, 1 in 5 had no symptoms, and 33% had tricuspid regurgitation velocity less than 2.8 m/s. No single measurement performed well in isolation in this study.³⁷

Thus, we recommend that, in addition to routine surface echocardiography, a multimodal approach be used that includes laboratory testing, clinical features, and electrocardiographic findings when screening this high-risk patient population.

Although macrovascular disease has not typically been regarded as a significant systemic feature in systemic sclerosis, myocardial infarction and stroke are more common in patients with systemic sclerosis than in controls.^38,39

Coronary artery disease in systemic sclerosis

Man et al³⁸ reported that the incidence of myocardial infarction in patients with systemic sclerosis was 4.4 per 1,000 persons per year, and the incidence of stroke was 4.8 per 1,000 persons per year, compared with 2.5 per 1,000 persons per year for both myocardial infarction and stroke in healthy controls matched for age, sex, and time of entry.

The Australian Scleroderma Cohort Study³⁹ found a 3-fold higher prevalence of coronary artery disease in systemic sclerosis patients than in controls after factoring in traditional risk factors.

Aviña-Zubieta et al,⁴⁰ in a cohort of 1,239 systemic sclerosis patients, estimated a hazard ratio (HR) of 3.49 for myocardial infarction and 2.35 for stroke compared with age- and sex-matched controls. Not all of these events were related to macrovascular atherosclerosis—vasospasm and microvascular ischemia may have played significant roles in the etiology of clinical manifestations.

Studies of coronary atherosclerosis in systemic sclerosis are limited. An autopsy study⁴¹ of 58 patients with systemic sclerosis and 58 controls matched for age, sex, and ethnicity found that the prevalence of atherosclerosis of small coronary arteries and arterioles was significantly higher in systemic sclerosis patients than in controls (17% vs 2%, P < .01). However, the prevalence of medium-vessel coronary atherosclerosis was similar (48% vs 43%).

Why patients with systemic sclerosis develop atherosclerosis has not yet been determined. Traditional risk factors such as hypertension, dyslipidemia, diabetes mellitus, and obesity are typically no more prevalent in systemic sclerosis patients than in controls,^38,42 and thus do not explain the increased risk of atherosclerotic cardiovascular disease. There is some evidence that novel markers of atherosclerotic risk such as homocysteine,⁴³ lipoprotein[a],⁴⁴ and oxidized low-density lipoprotein⁴⁵ are more prevalent in systemic sclerosis, but these results have not been substantiated in more extensive studies.

Peripheral artery disease

It remains unclear whether peripheral artery disease is more prevalent in systemic sclerosis patients than in controls.

Individual studies have shown mixed results in comparing carotid artery stenosis between systemic sclerosis patients and controls using carotid duplex ultrasonography,⁴⁶ the ankle-brachial index,^46–48 carotid intima-media thickness,^49–54 and brachial flow-mediated dilation.^{51,53,55–58} A meta-analysis found that the carotid intima and media are significantly thicker in systemic sclerosis patients than in controls,⁵⁹ and the magnitude of difference is similar to that in other groups at increased cardiovascular risk, such as those with rheumatoid arthritis, diabetes, and familial hypercholesterolemia.^60–63

A meta-analysis of brachial artery findings showed significantly lower flow-mediated dilation in systemic sclerosis patients than in controls.⁶⁴

Overall, given the inconsistency of study results, systemic sclerosis patients should be screened and managed as in other patients with peripheral artery disease, but the clinician should be aware that there may be a higher risk of peripheral artery disease in these patients.

RIGHT AND LEFT VENTRICULAR DYSFUNCTION

Many patients with systemic sclerosis have right ventricular dysfunction as a consequence of PAH.⁶⁵ It is important to detect diastolic dysfunction in this population, as it may be an even stronger predictor of death than pulmonary hypertension on right heart catheterization (HR 3.7 vs 2.0).⁶⁶

Fewer patients have left ventricular dysfunction. In a multicenter study of 570 systemic sclerosis patients, only 1.4% had left ventricular systolic dysfunction on echocardiography, though 22.6% had left ventricular hypertrophy and 17.7% had left ventricular diastolic dysfunction.⁶⁷ In the European League Against Rheumatism (EULAR) database, the prevalence of reduced left ventricular ejection fraction was 5.4%.⁶⁸

Though traditional echocardiographic screening suggests the prevalence of left ventricular dysfunction in systemic sclerosis patients is low, cardiac magnetic resonance imaging (MRI) may be more sensitive than echocardiography for detecting subclinical myocardial involvement. Cardiac MRI has been shown to detect evidence of myocardial pathology (increased T2 signal, left ventricular thinning, pericardial effusion, reduced left ventricular and right ventricular ejection fraction, left ventricular diastolic dysfunction, and delayed myocardial contrast enhancement) in up to 75% of systemic sclerosis cases studied.⁶⁹

Patients with systemic sclerosis should already be undergoing echocardiography every year to screen for PAH, and screening should also include tissue Doppler imaging to detect various forms of left and right ventricular systolic and diastolic dysfunction that may not be clinically apparent.

Though cardiac MRI can provide useful additional information, it is not currently recommended for routine screening in patients with systemic sclerosis.

Patients with systemic sclerosis are prone to arrhythmias due to both conduction system fibrosis and myocardial damage.

Arrhythmias accounted for 6% of the deaths in the EULAR Scleroderma Trials and Research (EUSTAR) database.¹¹

In the Genetics Versus Environment in Scleroderma Outcome Study (GENISOS),⁷⁰  250 patients who had had systemic sclerosis for at least 3 years were studied during a period of approximately 6 years, during which there were 52 deaths, 29 of which were directly attributable to systemic sclerosis. Multivariable Cox modeling showed that 7 variables predicted mortality:

• Body mass index < 18.5 kg/m²
• Age ≥ 65
• Forced vital capacity < 50% predicted
• Systolic blood pressure ≥ 140 or diastolic blood pressure ≥ 90 mm Hg
• Pulmonary fibrosis
• Positive anticentromere antibodies
• Cardiac arrhythmias.

The hazard ratio for death in patients with arrhythmias in this model was 2.18 (95% CI 1.05–4.50, P = .035). Thus, finding arrhythmias in systemic sclerosis patients can provide important prognostic information.

While resting electrocardiography in patients with systemic sclerosis  most commonly shows sinus rhythm, 24-hour electrocardiographic monitoring has revealed nonsustained supraventricular and ventricular arrhythmias in a significant percentage.^71,72 Although difficult to quantify in routine practice, parameters controlled by the autonomic nervous system including heart rate variability and heart rate turbulence have been shown to be impaired in systemic sclerosis, and these measures are associated with an increased risk of malignant arrhythmias and sudden cardiac death.^73,74

Conduction abnormalities

Conduction abnormalities occur in one-fifth to one-third of patients with systemic sclerosis.^75,76 The most common abnormal conduction finding is left bundle branch block, followed by first-degree atrioventricular block. High-degree atrioventricular block is uncommon,⁷⁶ though a few case reports of complete heart block thought to be related to systemic sclerosis have been published.^77–79 An autopsy study showed that the conduction system is relatively spared from myocardial changes seen in systemic sclerosis patients, and thus it is speculated that the conduction disturbances are a consequence of damaged myocardium rather than damage to conduction tissue.⁸⁰

Given the array of electrophysiologic abnormalities that systemic sclerosis patients can have, it is critical to monitor all patients with routine (annual or biannual) electrocardiography; to take possible arrhythmia-related symptoms seriously; and to evaluate them with further workup such as Holter monitoring for 24 hours or even longer, event monitoring, exercise testing, or tilt-table testing.

PERICARDIAL DISEASE

Pericardial disease is clinically apparent in 5% to 16% of patients with systemic sclerosis⁸¹; patients with limited cutaneous systemic sclerosis have more pericardial disease than those with diffuse cutaneous systemic sclerosis (30% vs 16%).⁸² Forty-one percent of systemic sclerosis patients have been shown to have pericardial effusion by echocardiography,⁸¹ but the effusions are typically small and rarely cause tamponade, though tamponade is associated with a poor prognosis.

Large pericardial effusions can develop before skin thickening and diagnosis of systemic sclerosis.^81,83,84 Thus, systemic sclerosis should be considered in patients with pericardial effusions of unknown etiology.

In a small study,⁸⁵ the pericardial fluid in systemic sclerosis was typically exudative, with lactate dehydrogenase greater than 200 U/L, a fluid-serum lactate dehydrogenase ratio greater than 0.6, and a fluid-serum total protein ratio greater than 0.5.

Pericardial effusion can be a sign of impending scleroderma renal crisis,⁸⁶ and thus renal function should be carefully monitored in systemic sclerosis patients with pericardial effusion. Constrictive pericarditis and restrictive cardiomyopathy can rarely occur in systemic sclerosis and may more commonly present with symptoms.

Pericardial disease in systemic sclerosis should be treated in a standard fashion with nonsteroidal anti-inflammatory drugs. Corticosteroids are generally of limited benefit and should be avoided, especially in the setting of scleroderma renal crisis.⁸¹

VALVULAR HEART DISEASE

Based on limited studies, the prevalence of significant valvular heart disease in systemic sclerosis patients does not seem to be higher than that in the general population. While patients with systemic sclerosis and CREST syndrome (calcinosis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia) have been shown to have a higher frequency of mitral valve prolapse and mild mitral regurgitation,^87,88 these abnormalities do not often progress in severity, and thus their clinical significance is limited.

It is important for physicians caring for patients with systemic sclerosis to be aware of its most common cardiac manifestations, including left and right ventricular systolic and diastolic dysfunction, pulmonary hypertension, conduction abnormalities, arrhythmias, and cardiomyopathy.

Look for volume overload

On clinical examination, assess for clinical markers of volume overload such as distended neck veins, peripheral edema, or an abnormal blood pressure response to the Valsalva maneuver. These findings should prompt measurement of NT-proBNP,⁸⁹ and may warrant prescription of a diuretic.

Electrocardiography to investigate arrhythmias

Electrocardiography should be done if patients describe symptoms of palpitations, and should also include continuous rhythm monitoring with Holter or event monitoring, depending on the frequency of symptoms. Otherwise, patients should routinely undergo electrocardiography once or twice a year.

Q waves are common in systemic sclerosis patients (especially those with diffuse cutaneous systemic sclerosis), notably in the precordial leads, and can occur without coronary artery disease.⁹⁰ Symptoms such as presyncope should be further investigated with Holter monitoring and tilt-table testing.

Assess, modify traditional risk factors

Subclinical atherosclerosis as detected by carotid intima-media thickness is as common in systemic sclerosis as in rheumatoid arthritis.⁶¹ However, traditional risk indices such as SCORE (Systematic Coronary Risk Evaluation), QRISK2, and the American College of Cardiology/American Heart Association indices may underestimate risk in patients who have systemic sclerosis.

Strict hypertension control should be the goal for all systemic sclerosis patients. Though there are no specific guidelines on which antihypertensive medications are preferred, calcium channel blockers or angiotensin II receptor blockers, which are typically used to treat systemic sclerosis-related Raynaud phenomenon, may be appropriate.

Statins reduce vascular complications and are generally well tolerated in patients with systemic sclerosis.^91,92 

Aspirin is not recommended for routine primary prevention in view of data suggesting that its benefits in diabetic patients are counterbalanced by increased bleeding risk.⁹³

Echocardiography to detect pulmonary arterial hypertension

At this time, guidelines for monitoring for cardiovascular manifestations in systemic sclerosis patients are limited. The only well-defined ones are European consensus guidelines, which suggest annual transthoracic echocardiography for the first 5 years after systemic sclerosis is diagnosed and continued annual screening in patients at risk of developing PAH.³¹

We support this strategy, with annual screening for the first 5 years followed by surveillance echocardiography every 2 to 3 years unless there is a high risk of PAH. Specific attention should be paid to right ventricular diastolic function, right atrial volume, and right ventricular myocardial performance index.

Emerging data suggest that the addition of global longitudinal strain of ventricles to  routine echocardiography can help detect subclinical cardiac risk.⁹⁴ Although further study is needed into the predictive value of global longitudinal strain, it is a low-cost and noninvasive addition to standard echocardiography that can help guide risk stratification, and thus we recommend that it be part of the echocardiographic examination for all systemic sclerosis patients.

Pulmonary function testing. In addition to screening for PAH with echocardiography, we recommend obtaining baseline pulmonary function tests, including D_^LCO, at the time systemic sclerosis is diagnosed, with repeat testing annually.

Magnetic resonance imaging

While echocardiography is the gold standard for monitoring systemic sclerosis patients, cardiovascular MRI may have a role in identifying those at higher risk of dangerous arrhythmias such as ventricular tachycardia and ventricular fibrillation. In addition to assessing ventricular function, MRI can detect myocardial inflammation, ischemia, and fibrosis that may predispose a patient to develop ventricular tachycardia or fibrillation.⁹⁵ Variables such as T1/T2 mapping, extracellular volume fraction, T2 signal ratio, and early vs late gadolinium enhancement can help identify patients who had past ventricular tachycardia or fibrillation.⁹⁶

Finding an increased risk of arrhythmias may prompt a conversation between the patient and the physician about the need for an implantable cardiac defibrillator.

If cardiac MRI is available and is reimbursed by the patient’s insurance carrier, physicians should strongly consider obtaining at least one baseline scan in systemic sclerosis patients to identify those at risk of highly fatal arrhythmias.

Teamwork is needed

Systemic sclerosis has not traditionally been associated with cardiovascular disease to the extent of other rheumatic conditions, but the cardiovascular system can be affected in various ways that can ultimately lead to an early death. These manifestations may be asymptomatic for long periods, and overt clinical disease portends a poorer prognosis.

Primary care physicians managing these patients should be aware of the cardiovascular complications of systemic sclerosis and should implement appropriate screening tests in conjunction with rheumatologists and cardiologists. It is also essential for general and subspecialty cardiologists to understand the broad spectrum of organ system involvement that can affect systemic sclerosis patients and to tailor their investigation and management recommendations accordingly. By designing a multidisciplinary approach to the treatment of systemic sclerosis patients, physicians can help to optimize cardiovascular risk modification in this vulnerable population.

A 78-year-old woman presented to the emergency department with shortness of breath and palpitations and was found to have atrial fibrillation with rapid ventricular response. Medical therapy with drug therapy and cardioversion proved ineffective. She then underwent atrioventricular node ablation and placement of a pacemaker.

At the time of admission, anticoagulation was started with full-dose enoxaparin, injected subcutaneously on the left side of the abdominal wall, as her CHA₂DS₂-VASc score (http://chadvasc.org) was 5, due to age, female sex, and history of heart failure and hypertension.

Four days after admission, she reported lower abdominal pain, and her urine output was minimal. A bladder scan showed more than 500 mL of residual urine. She was hemodynamically stable, but physical examination revealed mild abdominal distention and tenderness in the suprapubic region. Laboratory testing showed a sharp rise in serum creatinine and a drop in hematocrit.

The patient was initially managed conservatively with serial physical examinations, monitoring of the hematocrit, serial imaging studies, and discontinuation of anticoagulation, but the pain and anuria persisted. Repeat computed tomography 15 days after admission showed that the hematoma had expanded, and she now had hydronephrosis on the right side as well, requiring urologic intervention with bilateral nephrostomy tube placement.

The size of the hematoma was evaluated with serial abdominal and pelvic examinations. After several days, her urine output had improved, the nephrostomy tubes were removed, and she was discharged.

RECTUS SHEATH HEMATOMA

Our patient had a giant pelvic hematoma, probably arising from the rectus sheath. This uncommon problem can arise from trauma, anticoagulation, or increased intra-abdominal pressure, but it can also occur spontaneously.¹

In rectus sheath hematoma, a branch of the inferior epigastric artery is injured at its insertion into the rectus abdominis muscle. Symptoms arise if bleeding does not stop spontaneously from a tamponade effect.²

We speculate that in our patient, deep injection of enoxaparin into the abdominal wall injured the inferior epigastric artery, which started the hematoma, and the bleeding was exacerbated by the anticoagulation effect of the enoxaparin.

Another form of pelvic hematoma is retro­peritoneal. It is most commonly caused by trauma but can occur due to rupture of the aorta, compression from tumors, or, infrequently, anticoagulation therapy.³

The role of anticoagulation

Spontaneous pelvic hematoma is usually missed as a cause of abdominal pain in patients on anticoagulation therapy and is mistaken for common acute conditions such as ulcer, diverticulitis, appendicitis, ovarian cyst torsion, and tumor.⁴ It usually develops within 5 days of starting anticoagulation therapy. Symptoms vary depending on the location of the hematoma and are best diagnosed with abdominal computed tomography, with sensitivity as high as 100%.

MANAGEMENT

Conservative management, reserved for patients in stable condition, includes temporarily stopping and reevaluating the risks and benefits of anticoagulation and antiplatelet agents, giving blood transfusions, and controlling pain. If conservative measures fail, options are arterial embolization, stent grafting, and blood vessel ligation.⁵ If these measures fail, patients should undergo surgical evacuation of the hematoma and ligation of bleeding vessels.⁶

TAKE-HOME MESSAGE

Subcutaneous injections, especially of anticoagulants, into the abdominal wall can increase the risk of hematoma. Other risk factors are older age, female sex, and thin body habitus with less abdominal fat.⁷ Healthcare professionals should avoid deep injections into the abdomen and should counsel patients and their caregivers about this, as well. The deltoid region could be a safer alternative.

A 78-year-old woman presented to the emergency department with shortness of breath and palpitations and was found to have atrial fibrillation with rapid ventricular response. Medical therapy with drug therapy and cardioversion proved ineffective. She then underwent atrioventricular node ablation and placement of a pacemaker.

At the time of admission, anticoagulation was started with full-dose enoxaparin, injected subcutaneously on the left side of the abdominal wall, as her CHA₂DS₂-VASc score (http://chadvasc.org) was 5, due to age, female sex, and history of heart failure and hypertension.

Four days after admission, she reported lower abdominal pain, and her urine output was minimal. A bladder scan showed more than 500 mL of residual urine. She was hemodynamically stable, but physical examination revealed mild abdominal distention and tenderness in the suprapubic region. Laboratory testing showed a sharp rise in serum creatinine and a drop in hematocrit.

The patient was initially managed conservatively with serial physical examinations, monitoring of the hematocrit, serial imaging studies, and discontinuation of anticoagulation, but the pain and anuria persisted. Repeat computed tomography 15 days after admission showed that the hematoma had expanded, and she now had hydronephrosis on the right side as well, requiring urologic intervention with bilateral nephrostomy tube placement.

The size of the hematoma was evaluated with serial abdominal and pelvic examinations. After several days, her urine output had improved, the nephrostomy tubes were removed, and she was discharged.

RECTUS SHEATH HEMATOMA

Our patient had a giant pelvic hematoma, probably arising from the rectus sheath. This uncommon problem can arise from trauma, anticoagulation, or increased intra-abdominal pressure, but it can also occur spontaneously.¹

In rectus sheath hematoma, a branch of the inferior epigastric artery is injured at its insertion into the rectus abdominis muscle. Symptoms arise if bleeding does not stop spontaneously from a tamponade effect.²

We speculate that in our patient, deep injection of enoxaparin into the abdominal wall injured the inferior epigastric artery, which started the hematoma, and the bleeding was exacerbated by the anticoagulation effect of the enoxaparin.

Another form of pelvic hematoma is retro­peritoneal. It is most commonly caused by trauma but can occur due to rupture of the aorta, compression from tumors, or, infrequently, anticoagulation therapy.³

The role of anticoagulation

Spontaneous pelvic hematoma is usually missed as a cause of abdominal pain in patients on anticoagulation therapy and is mistaken for common acute conditions such as ulcer, diverticulitis, appendicitis, ovarian cyst torsion, and tumor.⁴ It usually develops within 5 days of starting anticoagulation therapy. Symptoms vary depending on the location of the hematoma and are best diagnosed with abdominal computed tomography, with sensitivity as high as 100%.

MANAGEMENT

Conservative management, reserved for patients in stable condition, includes temporarily stopping and reevaluating the risks and benefits of anticoagulation and antiplatelet agents, giving blood transfusions, and controlling pain. If conservative measures fail, options are arterial embolization, stent grafting, and blood vessel ligation.⁵ If these measures fail, patients should undergo surgical evacuation of the hematoma and ligation of bleeding vessels.⁶

TAKE-HOME MESSAGE

Subcutaneous injections, especially of anticoagulants, into the abdominal wall can increase the risk of hematoma. Other risk factors are older age, female sex, and thin body habitus with less abdominal fat.⁷ Healthcare professionals should avoid deep injections into the abdomen and should counsel patients and their caregivers about this, as well. The deltoid region could be a safer alternative.

A 78-year-old woman presented to the emergency department with shortness of breath and palpitations and was found to have atrial fibrillation with rapid ventricular response. Medical therapy with drug therapy and cardioversion proved ineffective. She then underwent atrioventricular node ablation and placement of a pacemaker.

At the time of admission, anticoagulation was started with full-dose enoxaparin, injected subcutaneously on the left side of the abdominal wall, as her CHA₂DS₂-VASc score (http://chadvasc.org) was 5, due to age, female sex, and history of heart failure and hypertension.

Four days after admission, she reported lower abdominal pain, and her urine output was minimal. A bladder scan showed more than 500 mL of residual urine. She was hemodynamically stable, but physical examination revealed mild abdominal distention and tenderness in the suprapubic region. Laboratory testing showed a sharp rise in serum creatinine and a drop in hematocrit.

The patient was initially managed conservatively with serial physical examinations, monitoring of the hematocrit, serial imaging studies, and discontinuation of anticoagulation, but the pain and anuria persisted. Repeat computed tomography 15 days after admission showed that the hematoma had expanded, and she now had hydronephrosis on the right side as well, requiring urologic intervention with bilateral nephrostomy tube placement.

The size of the hematoma was evaluated with serial abdominal and pelvic examinations. After several days, her urine output had improved, the nephrostomy tubes were removed, and she was discharged.

RECTUS SHEATH HEMATOMA

Our patient had a giant pelvic hematoma, probably arising from the rectus sheath. This uncommon problem can arise from trauma, anticoagulation, or increased intra-abdominal pressure, but it can also occur spontaneously.¹

In rectus sheath hematoma, a branch of the inferior epigastric artery is injured at its insertion into the rectus abdominis muscle. Symptoms arise if bleeding does not stop spontaneously from a tamponade effect.²

We speculate that in our patient, deep injection of enoxaparin into the abdominal wall injured the inferior epigastric artery, which started the hematoma, and the bleeding was exacerbated by the anticoagulation effect of the enoxaparin.

Another form of pelvic hematoma is retro­peritoneal. It is most commonly caused by trauma but can occur due to rupture of the aorta, compression from tumors, or, infrequently, anticoagulation therapy.³

The role of anticoagulation

Spontaneous pelvic hematoma is usually missed as a cause of abdominal pain in patients on anticoagulation therapy and is mistaken for common acute conditions such as ulcer, diverticulitis, appendicitis, ovarian cyst torsion, and tumor.⁴ It usually develops within 5 days of starting anticoagulation therapy. Symptoms vary depending on the location of the hematoma and are best diagnosed with abdominal computed tomography, with sensitivity as high as 100%.

MANAGEMENT

Conservative management, reserved for patients in stable condition, includes temporarily stopping and reevaluating the risks and benefits of anticoagulation and antiplatelet agents, giving blood transfusions, and controlling pain. If conservative measures fail, options are arterial embolization, stent grafting, and blood vessel ligation.⁵ If these measures fail, patients should undergo surgical evacuation of the hematoma and ligation of bleeding vessels.⁶

TAKE-HOME MESSAGE

Subcutaneous injections, especially of anticoagulants, into the abdominal wall can increase the risk of hematoma. Other risk factors are older age, female sex, and thin body habitus with less abdominal fat.⁷ Healthcare professionals should avoid deep injections into the abdomen and should counsel patients and their caregivers about this, as well. The deltoid region could be a safer alternative.

Background: POCUS is becoming more prevalent in the daily practice of hospitalists; however, there are currently no established standards or guidelines for the use of POCUS for hospitalists.

This position statement provides guidance on the use of POCUS by hospitalists and the administrators who oversee it by outlining POCUS in terms of common diagnostic and procedural applications; training; assessments by the categories of basic knowledge, image acquisition, interpretation, clinical integration, and certification and maintenance of skills; and program management.

Bottom line: This position statement by the SHM provides guidance for hospitalists and administrators on the use and oversight of POCUS.

Citation: Soni NJ et al. Point-of-care ultrasound for hospitalists: A position statement of the Society of Hospital Medicine. J Hosp Med. 2019 Jan 2;14:E1-E6.

Dr. Wang is an associate professor of medicine in the division of general and hospital medicine at UT Health San Antonio and a hospitalist at South Texas Veterans Health Care System.

Background: POCUS is becoming more prevalent in the daily practice of hospitalists; however, there are currently no established standards or guidelines for the use of POCUS for hospitalists.

This position statement provides guidance on the use of POCUS by hospitalists and the administrators who oversee it by outlining POCUS in terms of common diagnostic and procedural applications; training; assessments by the categories of basic knowledge, image acquisition, interpretation, clinical integration, and certification and maintenance of skills; and program management.

Bottom line: This position statement by the SHM provides guidance for hospitalists and administrators on the use and oversight of POCUS.

Citation: Soni NJ et al. Point-of-care ultrasound for hospitalists: A position statement of the Society of Hospital Medicine. J Hosp Med. 2019 Jan 2;14:E1-E6.

Dr. Wang is an associate professor of medicine in the division of general and hospital medicine at UT Health San Antonio and a hospitalist at South Texas Veterans Health Care System.

Background: POCUS is becoming more prevalent in the daily practice of hospitalists; however, there are currently no established standards or guidelines for the use of POCUS for hospitalists.

This position statement provides guidance on the use of POCUS by hospitalists and the administrators who oversee it by outlining POCUS in terms of common diagnostic and procedural applications; training; assessments by the categories of basic knowledge, image acquisition, interpretation, clinical integration, and certification and maintenance of skills; and program management.

Bottom line: This position statement by the SHM provides guidance for hospitalists and administrators on the use and oversight of POCUS.

Citation: Soni NJ et al. Point-of-care ultrasound for hospitalists: A position statement of the Society of Hospital Medicine. J Hosp Med. 2019 Jan 2;14:E1-E6.

Dr. Wang is an associate professor of medicine in the division of general and hospital medicine at UT Health San Antonio and a hospitalist at South Texas Veterans Health Care System.

Background: Abdominal paracentesis is a commonly performed procedure, and with appropriate training, hospitalists can deliver similar outcomes when compared to interventional radiologists.

To improve clinical outcomes, the authors recommended ultrasound guidance in performing paracentesis to reduce the risk of serious complications, to avoid attempting paracentesis with insufficient fluid, and to improve overall procedure success.

The authors advocated for several technique recommendations, including using the ultrasound to assess volume and location of intraperitoneal fluid, to identify the needle insertion site and confirm in multiple planes, to use color flow Doppler to identify abdominal wall vessels, to mark the insertion site immediately prior to the procedure, and to consider real-time ultrasound guidance.

When health care professionals are learning ultrasound-guided paracentesis, the authors recommended use of dedicated training sessions with simulation if available and that competency should be demonstrated before independently attempting the procedure.

Bottom line: These recommendations from SHM POCUS Task Force provides consensus guidelines on the use of ultrasound guidance when performing or learning abdominal paracentesis.

Citation: Cho J et al. Recommendations on the use of ultrasound guidance for adult abdominal paracentesis: A position statement of the Society of Hospital Medicine. 2019 Jan 2. doi: 10.12788/jhm.3095.

Dr. Schmit is an associate professor of medicine in the division of general and hospital medicine at UT Health San Antonio and a hospitalist at South Texas Veterans Health Care System, also in San Antonio.

Background: Abdominal paracentesis is a commonly performed procedure, and with appropriate training, hospitalists can deliver similar outcomes when compared to interventional radiologists.

To improve clinical outcomes, the authors recommended ultrasound guidance in performing paracentesis to reduce the risk of serious complications, to avoid attempting paracentesis with insufficient fluid, and to improve overall procedure success.

The authors advocated for several technique recommendations, including using the ultrasound to assess volume and location of intraperitoneal fluid, to identify the needle insertion site and confirm in multiple planes, to use color flow Doppler to identify abdominal wall vessels, to mark the insertion site immediately prior to the procedure, and to consider real-time ultrasound guidance.

When health care professionals are learning ultrasound-guided paracentesis, the authors recommended use of dedicated training sessions with simulation if available and that competency should be demonstrated before independently attempting the procedure.

Bottom line: These recommendations from SHM POCUS Task Force provides consensus guidelines on the use of ultrasound guidance when performing or learning abdominal paracentesis.

Citation: Cho J et al. Recommendations on the use of ultrasound guidance for adult abdominal paracentesis: A position statement of the Society of Hospital Medicine. 2019 Jan 2. doi: 10.12788/jhm.3095.

Dr. Schmit is an associate professor of medicine in the division of general and hospital medicine at UT Health San Antonio and a hospitalist at South Texas Veterans Health Care System, also in San Antonio.

Background: Abdominal paracentesis is a commonly performed procedure, and with appropriate training, hospitalists can deliver similar outcomes when compared to interventional radiologists.

To improve clinical outcomes, the authors recommended ultrasound guidance in performing paracentesis to reduce the risk of serious complications, to avoid attempting paracentesis with insufficient fluid, and to improve overall procedure success.

The authors advocated for several technique recommendations, including using the ultrasound to assess volume and location of intraperitoneal fluid, to identify the needle insertion site and confirm in multiple planes, to use color flow Doppler to identify abdominal wall vessels, to mark the insertion site immediately prior to the procedure, and to consider real-time ultrasound guidance.

When health care professionals are learning ultrasound-guided paracentesis, the authors recommended use of dedicated training sessions with simulation if available and that competency should be demonstrated before independently attempting the procedure.

Bottom line: These recommendations from SHM POCUS Task Force provides consensus guidelines on the use of ultrasound guidance when performing or learning abdominal paracentesis.

Citation: Cho J et al. Recommendations on the use of ultrasound guidance for adult abdominal paracentesis: A position statement of the Society of Hospital Medicine. 2019 Jan 2. doi: 10.12788/jhm.3095.

Dr. Schmit is an associate professor of medicine in the division of general and hospital medicine at UT Health San Antonio and a hospitalist at South Texas Veterans Health Care System, also in San Antonio.

A 50-year-old man with Crohn disease and psoriatic arthritis treated with infliximab and methotrexate presented to a tertiary care hospital with fever, cough, and chest discomfort. The symptoms had first appeared 2 weeks earlier, and he had gone to an urgent care center, where he was prescribed a 5-day course of azithromycin and a corticosteroid, but this had not relieved his symptoms.

Bronchoscopy revealed edematous mucosa throughout, with minimal secretion. Specimens for bacterial, acid-fast bacillus, and fungal cultures were obtained from bronchoalveolar lavage. Endobronchial lymph node biopsy with ultrasonographic guidance revealed nonnecrotizing granuloma.

Bronchoalveolar lavage cultures showed no growth, but the patient’s serum histoplasma antigen was positive at 5.99 ng/dL (reference range: none detected), leading to the diagnosis of mediastinal granuloma due to histoplasmosis with possible dissemination. His immunosuppressant drugs were stopped, and oral itraconazole was started.

At a follow-up visit 2 months later, his serum antigen level had decreased to 0.68 ng/dL, and he had no symptoms whatsoever. At a visit 1 month after that, infliximab and methotrexate were restarted because of an exacerbation of Crohn disease. His oral itraconazole treatment was to be continued for at least 12 months, given the high suspicion for disseminated histoplasmosis while on immunosuppressant therapy.

DIFFERENTIAL DIAGNOSIS OF GRANULOMATOUS LUNG DISEASE AND LYMPHADENOPATHY

The differential diagnosis of granulomatous lung disease and lymphadenopathy is broad and includes noninfectious and infectious conditions.¹

Noninfectious causes include lymphoma, sarcoidosis, inflammatory bowel disease, hypersensitivity pneumonia, side effects of drugs (eg, methotrexate, etanercept), rheumatoid nodules, vasculitis (eg, Churg-Strauss syndrome, granulomatosis with polyangiitis, primary amyloidosis, pneumoconiosis (eg, beryllium, cobalt), and Castleman disease.

There is concern that tumor necrosis factor antagonists may increase the risk of lymphoma, but a 2017 study found no evidence of this.²

Infectious conditions associated with granulomatous lung disease include tuberculosis, nontuberculous mycobacterial infection, fungal infection (eg, Cryptococcus, Coccidioides, Histoplasma, Blastomyces), brucellosis, tularemia (respiratory type B), parasitic infection (eg, Toxocara, Leishmania, Echinococcus, Schistosoma), and Whipple disease.

HISTOPLASMOSIS

Histoplasmosis, caused by infection with Histoplasma capsulatum, is the most prevalent endemic mycotic disease in the United States.³ The fungus is commonly found in the Ohio and Mississippi River valleys in the United States, and also in Central and South America and Asia.

Risk factors for histoplasmosis include living in or traveling to an endemic area, exposure to aerosolized soil that contains spores, and exposure to bats or birds and their droppings.⁴

Fewer than 5% of exposed individuals develop symptoms, which include fever, chills, headache, myalgia, anorexia, cough, and chest pain.⁵ Patients may experience symptoms shortly after exposure or may remain free of symptoms for years, with intermittent relapses of symptoms.⁶ Hilar or mediastinal lymphadenopathy is common in acute pulmonary histoplasmosis.⁷

The risk of disseminated histoplasmosis is greater in patients with reduced cell-mediated immunity, such as in human immunodeficiency virus infection, acquired immunodeficiency syndrome, solid-organ or bone marrow transplant, hematologic malignancies, immunosuppression (corticosteroids, disease-modifying antirheumatic drugs, and tumor necrosis factor antagonists), and congenital T-cell deficiencies.⁸

In a retrospective study, infliximab was the tumor necrosis factor antagonist most commonly associated with histoplasmosis.⁹ In a study of patients with rheumatoid arthritis, the disease-modifying drug most commonly associated was methotrexate.¹⁰

Isolation of H capsulatum from clinical specimens remains the gold standard for confirmation of histoplasmosis. The sensitivity of culture to detect H capsulatum depends on the clinical manifestations: it is 74% in patients with disseminated histoplasmosis, but only 42% in patients with acute pulmonary histoplasmosis.¹¹ The serum histoplasma antigen test has a sensitivity of 91.8% in disseminated histoplasmosis, 87.5% in chronic pulmonary histoplasmosis, and 83% in acute pulmonary histoplasmosis.¹²

Urine testing for histoplasma antigen has generally proven to be slightly more sensitive than serum testing in all manifestations of histoplasmosis.¹³ Combining urine and serum testing increases the likelihood of antigen detection.

TREATMENT

Asymptomatic patients with mediastinal histoplasmosis do not require treatment. (Note: in some cases, lymphadenopathy is found incidentally, and biopsy is done to rule out malignancy.)

Standard treatment of symptomatic mediastinal histoplasmosis is oral itraconazole 200 mg, 3 times daily for 3 days, followed by 200 mg orally once or twice daily for 6 to 12 weeks.¹⁴

Although stopping immunosuppressant drugs is considered the standard of care in treating histoplasmosis in immunocompromised patients, there are no guidelines on when to resume them. However, a retrospective study of 98 cases of histoplasmosis in patients on tumor necrosis factor antagonists found that resuming immunosuppressants might be safe with close monitoring during the course of antifungal therapy.⁹ The role of long-term suppressive therapy with antifungal agents in patients on chronic immunosuppressive therapy is still unknown and needs further study.

TAKE-HOME MESSAGES

• Histoplasmosis is the most prevalent endemic mycotic disease in the United States, and mediastinal lymphadenopathy is commonly seen in acute pulmonary histoplasmosis.
• Histoplasmosis should be included in the differential diagnosis of granulomatous lung disease in patients from an endemic area or with a history of travel to an endemic area.
• Immunosuppressive agents such as tumor necrosis factor antagonists and disease-modifying antirheumatic drugs can predispose to invasive fungal infection, including histoplasmosis.
• While isolation of H capsulatum from culture remains the gold standard for the diagnosis of histoplasmosis, the histoplasma antigen tests (serum and urine) is more sensitive than culture.

A 50-year-old man with Crohn disease and psoriatic arthritis treated with infliximab and methotrexate presented to a tertiary care hospital with fever, cough, and chest discomfort. The symptoms had first appeared 2 weeks earlier, and he had gone to an urgent care center, where he was prescribed a 5-day course of azithromycin and a corticosteroid, but this had not relieved his symptoms.

Bronchoscopy revealed edematous mucosa throughout, with minimal secretion. Specimens for bacterial, acid-fast bacillus, and fungal cultures were obtained from bronchoalveolar lavage. Endobronchial lymph node biopsy with ultrasonographic guidance revealed nonnecrotizing granuloma.

Bronchoalveolar lavage cultures showed no growth, but the patient’s serum histoplasma antigen was positive at 5.99 ng/dL (reference range: none detected), leading to the diagnosis of mediastinal granuloma due to histoplasmosis with possible dissemination. His immunosuppressant drugs were stopped, and oral itraconazole was started.

At a follow-up visit 2 months later, his serum antigen level had decreased to 0.68 ng/dL, and he had no symptoms whatsoever. At a visit 1 month after that, infliximab and methotrexate were restarted because of an exacerbation of Crohn disease. His oral itraconazole treatment was to be continued for at least 12 months, given the high suspicion for disseminated histoplasmosis while on immunosuppressant therapy.

DIFFERENTIAL DIAGNOSIS OF GRANULOMATOUS LUNG DISEASE AND LYMPHADENOPATHY

The differential diagnosis of granulomatous lung disease and lymphadenopathy is broad and includes noninfectious and infectious conditions.¹

Noninfectious causes include lymphoma, sarcoidosis, inflammatory bowel disease, hypersensitivity pneumonia, side effects of drugs (eg, methotrexate, etanercept), rheumatoid nodules, vasculitis (eg, Churg-Strauss syndrome, granulomatosis with polyangiitis, primary amyloidosis, pneumoconiosis (eg, beryllium, cobalt), and Castleman disease.

There is concern that tumor necrosis factor antagonists may increase the risk of lymphoma, but a 2017 study found no evidence of this.²

Infectious conditions associated with granulomatous lung disease include tuberculosis, nontuberculous mycobacterial infection, fungal infection (eg, Cryptococcus, Coccidioides, Histoplasma, Blastomyces), brucellosis, tularemia (respiratory type B), parasitic infection (eg, Toxocara, Leishmania, Echinococcus, Schistosoma), and Whipple disease.

HISTOPLASMOSIS

Histoplasmosis, caused by infection with Histoplasma capsulatum, is the most prevalent endemic mycotic disease in the United States.³ The fungus is commonly found in the Ohio and Mississippi River valleys in the United States, and also in Central and South America and Asia.

Risk factors for histoplasmosis include living in or traveling to an endemic area, exposure to aerosolized soil that contains spores, and exposure to bats or birds and their droppings.⁴

Fewer than 5% of exposed individuals develop symptoms, which include fever, chills, headache, myalgia, anorexia, cough, and chest pain.⁵ Patients may experience symptoms shortly after exposure or may remain free of symptoms for years, with intermittent relapses of symptoms.⁶ Hilar or mediastinal lymphadenopathy is common in acute pulmonary histoplasmosis.⁷

The risk of disseminated histoplasmosis is greater in patients with reduced cell-mediated immunity, such as in human immunodeficiency virus infection, acquired immunodeficiency syndrome, solid-organ or bone marrow transplant, hematologic malignancies, immunosuppression (corticosteroids, disease-modifying antirheumatic drugs, and tumor necrosis factor antagonists), and congenital T-cell deficiencies.⁸

In a retrospective study, infliximab was the tumor necrosis factor antagonist most commonly associated with histoplasmosis.⁹ In a study of patients with rheumatoid arthritis, the disease-modifying drug most commonly associated was methotrexate.¹⁰

Isolation of H capsulatum from clinical specimens remains the gold standard for confirmation of histoplasmosis. The sensitivity of culture to detect H capsulatum depends on the clinical manifestations: it is 74% in patients with disseminated histoplasmosis, but only 42% in patients with acute pulmonary histoplasmosis.¹¹ The serum histoplasma antigen test has a sensitivity of 91.8% in disseminated histoplasmosis, 87.5% in chronic pulmonary histoplasmosis, and 83% in acute pulmonary histoplasmosis.¹²

Urine testing for histoplasma antigen has generally proven to be slightly more sensitive than serum testing in all manifestations of histoplasmosis.¹³ Combining urine and serum testing increases the likelihood of antigen detection.

TREATMENT

Asymptomatic patients with mediastinal histoplasmosis do not require treatment. (Note: in some cases, lymphadenopathy is found incidentally, and biopsy is done to rule out malignancy.)

Standard treatment of symptomatic mediastinal histoplasmosis is oral itraconazole 200 mg, 3 times daily for 3 days, followed by 200 mg orally once or twice daily for 6 to 12 weeks.¹⁴

Although stopping immunosuppressant drugs is considered the standard of care in treating histoplasmosis in immunocompromised patients, there are no guidelines on when to resume them. However, a retrospective study of 98 cases of histoplasmosis in patients on tumor necrosis factor antagonists found that resuming immunosuppressants might be safe with close monitoring during the course of antifungal therapy.⁹ The role of long-term suppressive therapy with antifungal agents in patients on chronic immunosuppressive therapy is still unknown and needs further study.

TAKE-HOME MESSAGES

• Histoplasmosis is the most prevalent endemic mycotic disease in the United States, and mediastinal lymphadenopathy is commonly seen in acute pulmonary histoplasmosis.
• Histoplasmosis should be included in the differential diagnosis of granulomatous lung disease in patients from an endemic area or with a history of travel to an endemic area.
• Immunosuppressive agents such as tumor necrosis factor antagonists and disease-modifying antirheumatic drugs can predispose to invasive fungal infection, including histoplasmosis.
• While isolation of H capsulatum from culture remains the gold standard for the diagnosis of histoplasmosis, the histoplasma antigen tests (serum and urine) is more sensitive than culture.

A 50-year-old man with Crohn disease and psoriatic arthritis treated with infliximab and methotrexate presented to a tertiary care hospital with fever, cough, and chest discomfort. The symptoms had first appeared 2 weeks earlier, and he had gone to an urgent care center, where he was prescribed a 5-day course of azithromycin and a corticosteroid, but this had not relieved his symptoms.

Bronchoscopy revealed edematous mucosa throughout, with minimal secretion. Specimens for bacterial, acid-fast bacillus, and fungal cultures were obtained from bronchoalveolar lavage. Endobronchial lymph node biopsy with ultrasonographic guidance revealed nonnecrotizing granuloma.

Bronchoalveolar lavage cultures showed no growth, but the patient’s serum histoplasma antigen was positive at 5.99 ng/dL (reference range: none detected), leading to the diagnosis of mediastinal granuloma due to histoplasmosis with possible dissemination. His immunosuppressant drugs were stopped, and oral itraconazole was started.

At a follow-up visit 2 months later, his serum antigen level had decreased to 0.68 ng/dL, and he had no symptoms whatsoever. At a visit 1 month after that, infliximab and methotrexate were restarted because of an exacerbation of Crohn disease. His oral itraconazole treatment was to be continued for at least 12 months, given the high suspicion for disseminated histoplasmosis while on immunosuppressant therapy.

DIFFERENTIAL DIAGNOSIS OF GRANULOMATOUS LUNG DISEASE AND LYMPHADENOPATHY

The differential diagnosis of granulomatous lung disease and lymphadenopathy is broad and includes noninfectious and infectious conditions.¹

Noninfectious causes include lymphoma, sarcoidosis, inflammatory bowel disease, hypersensitivity pneumonia, side effects of drugs (eg, methotrexate, etanercept), rheumatoid nodules, vasculitis (eg, Churg-Strauss syndrome, granulomatosis with polyangiitis, primary amyloidosis, pneumoconiosis (eg, beryllium, cobalt), and Castleman disease.

There is concern that tumor necrosis factor antagonists may increase the risk of lymphoma, but a 2017 study found no evidence of this.²

Infectious conditions associated with granulomatous lung disease include tuberculosis, nontuberculous mycobacterial infection, fungal infection (eg, Cryptococcus, Coccidioides, Histoplasma, Blastomyces), brucellosis, tularemia (respiratory type B), parasitic infection (eg, Toxocara, Leishmania, Echinococcus, Schistosoma), and Whipple disease.

HISTOPLASMOSIS

Histoplasmosis, caused by infection with Histoplasma capsulatum, is the most prevalent endemic mycotic disease in the United States.³ The fungus is commonly found in the Ohio and Mississippi River valleys in the United States, and also in Central and South America and Asia.

Risk factors for histoplasmosis include living in or traveling to an endemic area, exposure to aerosolized soil that contains spores, and exposure to bats or birds and their droppings.⁴

Fewer than 5% of exposed individuals develop symptoms, which include fever, chills, headache, myalgia, anorexia, cough, and chest pain.⁵ Patients may experience symptoms shortly after exposure or may remain free of symptoms for years, with intermittent relapses of symptoms.⁶ Hilar or mediastinal lymphadenopathy is common in acute pulmonary histoplasmosis.⁷

The risk of disseminated histoplasmosis is greater in patients with reduced cell-mediated immunity, such as in human immunodeficiency virus infection, acquired immunodeficiency syndrome, solid-organ or bone marrow transplant, hematologic malignancies, immunosuppression (corticosteroids, disease-modifying antirheumatic drugs, and tumor necrosis factor antagonists), and congenital T-cell deficiencies.⁸

In a retrospective study, infliximab was the tumor necrosis factor antagonist most commonly associated with histoplasmosis.⁹ In a study of patients with rheumatoid arthritis, the disease-modifying drug most commonly associated was methotrexate.¹⁰

Isolation of H capsulatum from clinical specimens remains the gold standard for confirmation of histoplasmosis. The sensitivity of culture to detect H capsulatum depends on the clinical manifestations: it is 74% in patients with disseminated histoplasmosis, but only 42% in patients with acute pulmonary histoplasmosis.¹¹ The serum histoplasma antigen test has a sensitivity of 91.8% in disseminated histoplasmosis, 87.5% in chronic pulmonary histoplasmosis, and 83% in acute pulmonary histoplasmosis.¹²

Urine testing for histoplasma antigen has generally proven to be slightly more sensitive than serum testing in all manifestations of histoplasmosis.¹³ Combining urine and serum testing increases the likelihood of antigen detection.

TREATMENT

Asymptomatic patients with mediastinal histoplasmosis do not require treatment. (Note: in some cases, lymphadenopathy is found incidentally, and biopsy is done to rule out malignancy.)

Standard treatment of symptomatic mediastinal histoplasmosis is oral itraconazole 200 mg, 3 times daily for 3 days, followed by 200 mg orally once or twice daily for 6 to 12 weeks.¹⁴

Although stopping immunosuppressant drugs is considered the standard of care in treating histoplasmosis in immunocompromised patients, there are no guidelines on when to resume them. However, a retrospective study of 98 cases of histoplasmosis in patients on tumor necrosis factor antagonists found that resuming immunosuppressants might be safe with close monitoring during the course of antifungal therapy.⁹ The role of long-term suppressive therapy with antifungal agents in patients on chronic immunosuppressive therapy is still unknown and needs further study.

TAKE-HOME MESSAGES

• Histoplasmosis is the most prevalent endemic mycotic disease in the United States, and mediastinal lymphadenopathy is commonly seen in acute pulmonary histoplasmosis.
• Histoplasmosis should be included in the differential diagnosis of granulomatous lung disease in patients from an endemic area or with a history of travel to an endemic area.
• Immunosuppressive agents such as tumor necrosis factor antagonists and disease-modifying antirheumatic drugs can predispose to invasive fungal infection, including histoplasmosis.
• While isolation of H capsulatum from culture remains the gold standard for the diagnosis of histoplasmosis, the histoplasma antigen tests (serum and urine) is more sensitive than culture.

No, they are not required or needed, but daily radiography and arterial blood gas testing are common practice: eg, 60% of intensive care unit (ICU) patients get daily radiographs,¹ even though results provide low diagnostic yield and are unlikely to alter patient management compared with testing only when indicated.

The Choosing Wisely campaign,² a collaborative effort of a number of professional societies, advises against ordering these diagnostic tests daily because routine testing increases risks to patients and burdens the healthcare system. Instead, testing is recommended only in response to a specific clinical question, or when the test results will affect the patient’s treatment.

CHEST RADIOGRAPHS: DAILY VS CLINICALLY INDICATED

Chest radiographs enable practitioners to monitor the position of endotracheal tubes and central venous catheters, evaluate fluid status, follow up on abnormal findings, detect complications of procedures (such as a pneumothorax), and identify otherwise undetected conditions.

And daily chest radiographs often detect abnormalities. A 1991 study by Hall et al³ of 538 chest radiographs in 74 patients on mechanical ventilation reported that 30% of daily routine chest radiographs disclosed a new but minor finding (eg, a small change in endotracheal tube position or a small infiltrate). The new findings were major in 13 (17.6%) of the 74 patients (95% confidence interval [CI] 9%–26%). These included findings that required an immediate diagnostic or therapeutic intervention (eg, endotracheal tube below the tracheal carina, malposition of a catheter, pneumothorax, large pleural effusion).

But most studies say daily radiographs are not needed. In a large prospective study published in 2006, Graat et al⁴ evaluated the clinical value of 2,457 routine chest radiographs in 754 patients in a combined surgical and medical ICU. Daily chest radiographs revealed new or unexpected findings in 5.8% of cases, but only 2.2% warranted a change in therapy. No differences were found between the medical and surgical patients. The authors concluded that daily routine radiographs in ICU patients seldom reveal unexpected, clinically relevant abnormalities, and those findings rarely require urgent intervention.

A 2010 meta-analysis of 8 studies (7,078 patients) by Oba and Zaza⁵ compared on-demand and daily routine strategies of performing chest radiographs. They estimated that eliminating daily routine chest radiographs would not affect death rates in the hospital (odds ratio [OR] 1.02, 95% CI 0.89–1.17, P = .78) or the ICU (OR 0.92, 95% CI 0.76–1.11, P = .4). They also found no significant differences in length of stay or duration of mechanical ventilation. This meta-analysis suggests that routine radiographs can be eliminated without adversely affecting outcomes in ICU patients.

A larger meta-analysis (9 trials, 39,358 radiographs, 9,611 patients) published in 2012 by Ganapathy et al⁶ also found no harm associated with restrictive radiography protocols. These investigators compared a daily chest radiography protocol against a protocol based on clinical indications. The primary outcome was the mortality rate in the ICU; secondary outcomes were the mortality rate in the hospital, the length of stay in the ICU, and duration of mechanical ventilation. They found no differences between routine and restrictive strategies in terms of ICU mortality (risk ratio [RR] 1.04, 95% CI 0.84–1.28, P = .72), hospital mortality (RR 0.98, 95% CI 0.68–1.41, P = .91), or other secondary outcomes.

Clinically indicated testing is better

The conclusion from these studies is that routine chest radiographs in patients undergoing mechanical ventilation does not improve patient outcomes, and thus, a clinically indicated protocol is preferred.

Furthermore, routine daily radiographs have adverse effects such as more cumulative radiation exposure to the patient⁷ and greater risk of accidental removal of devices (eg, catheters, tubes).⁸ Another concern is a higher risk of hospital-associated infections from bacterial spread from caregivers’ hands.⁹

Finally, daily radiographs increase the use of healthcare resources and expenditures. In a 2011 study, Gershengorn et al¹ estimated that adopting a clinically indicated radiography strategy could save more than $144 million annually in the United States.

The ACR agrees. Appropriateness criteria published by the American College of Radiology (ACR) in 2015¹⁰ recommend against routine daily chest radiographs in the ICU, in keeping with the findings of the critical care community. The ACR recommends an initial radiograph at admission to the ICU. However, follow-up radiographs should be obtained only for specific clinical indications, including a change in the patient’s clinical condition or to check for proper placement of endotracheal or nasogastric or orogastric tubes, pulmonary arterial catheters, central venous catheters, chest tubes, and other life-support devices.

Ultrasonography as an alternative

Ultrasonography is widely available and provides an alternative to chest radiography for detecting significant abnormalities in patients on mechanical ventilation without exposing them to radiation and using relatively fewer resources.

A 2012 meta-analysis (8 studies, 1,048 patients) found that bedside ultrasonography reliably detects pneumothorax.¹¹ It can also provide a rapid diagnosis of the cause of acute respiratory failure such as pneumonia or pulmonary edema.¹² Ultrasonography, with the appropriate expertise, can also confirm the position of an endotracheal tube¹³ or central venous catheter.¹⁴

Arterial blood gas testing has value for managing patients undergoing mechanical ventilation, and it is one of the most commonly performed diagnostic tests in the ICU. It provides reliable information about the patient’s oxygenation and acid-base status. It is commonly requested when changing ventilator settings.

Downsides. Arterial blood gas measurements account for 10% to 20% of the cost incurred during ICU stay.¹⁵ In addition, they require an arterial puncture—an invasive procedure associated with potentially serious complications such as occlusion of the artery, digital embolization leading to digital ischemia, local infection, pseudoaneurysm, hematoma, bleeding, and skin necrosis.

Is daily testing needed?

Guidelines say no. The 2013 American Association for Respiratory Care¹⁶ guidelines suggest that arterial blood gas testing should be based on the clinical assessment of the patient. They recommend blood gas analysis to evaluate the patient’s ventilatory status (reflected by the partial pressure of arterial carbon dioxide [PaCO₂], acid-base status (reflected by pH), arterial oxygenation (partial pressure of arterial oxygen [PaO₂] and oxyhemoglobin saturation), oxygen-carrying capacity, and whether the patient likely has an intrapulmonary shunt. They state that testing is useful to quantify the response to therapeutic or diagnostic interventions such as cardiopulmonary exercise testing, to monitor severity and progression of documented disease, and to assess the adequacy of circulatory response.

Studies agree

The ACR recommendation to test “as clinically indicated” is supported by studies showing that patient outcomes are not inferior for arterial blood gas testing when clinically indicated instead of daily, and that this practice is associated with fewer complications, less resource use, and reduced overall patient care costs.

A 2015 study compared the efficacy and safety of obtaining arterial blood gases based on clinical assessment vs daily in 300 critically ill patients.¹⁷ Overall, fewer samples were obtained per patient in the clinical assessment group than in the daily group (all patients 3.7 vs 5.5; ventilated patients 2.03 vs 6.12; P < .001 for both). In ventilated patients, there was a 60% decrease in arterial blood gas orders without affecting patient outcomes and safety, including a lower risk of complications and overall cost of care.

In another study, Martinez-Balzano et al¹⁸ evaluated the effect of guidelines they developed to optimize the use of arterial blood gas testing in their ICUs. These guidelines encouraged testing of arterial blood gases after an acute respiratory event or for a rational clinical concern, and discouraged testing for routine surveillance, after planned changes of positive end-expiratory pressure or inspired oxygen fraction on mechanical ventilation, for spontaneous breathing trials, or when a disorder was not suspected.

Compared with data collected before implementation, these guidelines reduced the number of arterial blood gas tests by 821.5 per month (41.5%), or approximately 1 test per patient per mechanical-ventilation day for each month (43.1%; P < .001). Appropriately indicated testing rose to 83.4% from a baseline of 67.5% (P = .002). Additionally, this approach was associated with saving 49 liters of blood, reducing ICU costs by $39,432, and freeing up 1,643 staff work hours for other tasks. There were no significant differences in days on mechanical ventilation, severity of illness, or mortality between the 2 periods.¹⁸

Extubation effects. Routine arterial blood gas testing has not been shown to affect extubation decisions in patients on mechanical ventilation. In a study of 83 patients who completed a spontaneous breathing trial (total of 100 trials), Salam et al¹⁹ found arterial blood gas values obtained during the trial did not change the extubation decision in 93% of the cases.

In a study of 54 extubations in 52 patients,²⁰ 65% of the extubations were performed without obtaining an arterial blood gas test after the patient completed a trial of spontaneous breathing. The extubation success rate was 94% for the entire group, and it was the same regardless of whether testing was done (94.7% vs 94.3%, respectively).

Alternatives to arterial blood gases

There are less-invasive means to obtain the information that comes from an arterial blood gas test.

Pulse oximetry is a rapid noninvasive tool that provides continuous assessment of peripheral arterial oxygen saturation as a surrogate marker for tissue arterial oxygenation. However, it cannot measure PaO₂ or PaCO₂.²¹

Transcutaneous carbon dioxide (PTCO₂) monitoring is another continuous noninvasive alternative. The newer PTCO₂ devices are useful in patients with acute respiratory failure and in critically ill patients on vasopressors or vasodilators. Studies have shown good correlation between PTCO₂ and PaCO₂.^22,23

End-tidal carbon dioxide (PetCO₂) is another alternative to estimate PaCO₂. It can also be used to confirm endotracheal tube placement, during transportation, during procedures in which the patient is under conscious sedation, and to monitor the effectiveness of cardiopulmonary resuscitation and return of circulation after cardiac arrest. PetCO₂ measurements are not as accurate as arterial blood gas testing owing to a difference of approximately 2 to 5 mm Hg between PaCO₂ and PetCO₂ in normal lungs due to alveolar dead space. This difference may be much higher depending on the clinical condition and the degree of alveolar dead space.^21,24,25

Venous blood gases, which can be obtained from a peripheral or central venous catheter, are adequate to assess pH and partial pressure of carbon dioxide (PCO₂) in hemodynamically stable patients. Walkey et al²⁶ found that the accuracy of venous blood gas measurement to predict arterial blood gases was 90%. They recommended adjusting the venous pH up by 0.05 and the PCO₂ down by 5 mm Hg to account for the positive bias of venous blood gases. A limitation of this method is that the values are not reliable in patients who are in shock.

These alternatives can be used as a substitute for daily arterial blood gases. However, in certain clinical scenarios, arterial blood gas measurement remains a necessary and useful clinical tool.

TAKE-HOME MESSAGE

Most scientific evidence suggests that chest radiographs and arterial blood gas measurement in patients undergoing mechanical ventilation—and critically ill, in general—are best done when clinically indicated rather than routinely on a daily basis. This will reduce cost and harm to patients that may result from these unnecessary tests and not adversely affect outcomes.

No, they are not required or needed, but daily radiography and arterial blood gas testing are common practice: eg, 60% of intensive care unit (ICU) patients get daily radiographs,¹ even though results provide low diagnostic yield and are unlikely to alter patient management compared with testing only when indicated.

The Choosing Wisely campaign,² a collaborative effort of a number of professional societies, advises against ordering these diagnostic tests daily because routine testing increases risks to patients and burdens the healthcare system. Instead, testing is recommended only in response to a specific clinical question, or when the test results will affect the patient’s treatment.

CHEST RADIOGRAPHS: DAILY VS CLINICALLY INDICATED

Chest radiographs enable practitioners to monitor the position of endotracheal tubes and central venous catheters, evaluate fluid status, follow up on abnormal findings, detect complications of procedures (such as a pneumothorax), and identify otherwise undetected conditions.

And daily chest radiographs often detect abnormalities. A 1991 study by Hall et al³ of 538 chest radiographs in 74 patients on mechanical ventilation reported that 30% of daily routine chest radiographs disclosed a new but minor finding (eg, a small change in endotracheal tube position or a small infiltrate). The new findings were major in 13 (17.6%) of the 74 patients (95% confidence interval [CI] 9%–26%). These included findings that required an immediate diagnostic or therapeutic intervention (eg, endotracheal tube below the tracheal carina, malposition of a catheter, pneumothorax, large pleural effusion).

But most studies say daily radiographs are not needed. In a large prospective study published in 2006, Graat et al⁴ evaluated the clinical value of 2,457 routine chest radiographs in 754 patients in a combined surgical and medical ICU. Daily chest radiographs revealed new or unexpected findings in 5.8% of cases, but only 2.2% warranted a change in therapy. No differences were found between the medical and surgical patients. The authors concluded that daily routine radiographs in ICU patients seldom reveal unexpected, clinically relevant abnormalities, and those findings rarely require urgent intervention.

A 2010 meta-analysis of 8 studies (7,078 patients) by Oba and Zaza⁵ compared on-demand and daily routine strategies of performing chest radiographs. They estimated that eliminating daily routine chest radiographs would not affect death rates in the hospital (odds ratio [OR] 1.02, 95% CI 0.89–1.17, P = .78) or the ICU (OR 0.92, 95% CI 0.76–1.11, P = .4). They also found no significant differences in length of stay or duration of mechanical ventilation. This meta-analysis suggests that routine radiographs can be eliminated without adversely affecting outcomes in ICU patients.

A larger meta-analysis (9 trials, 39,358 radiographs, 9,611 patients) published in 2012 by Ganapathy et al⁶ also found no harm associated with restrictive radiography protocols. These investigators compared a daily chest radiography protocol against a protocol based on clinical indications. The primary outcome was the mortality rate in the ICU; secondary outcomes were the mortality rate in the hospital, the length of stay in the ICU, and duration of mechanical ventilation. They found no differences between routine and restrictive strategies in terms of ICU mortality (risk ratio [RR] 1.04, 95% CI 0.84–1.28, P = .72), hospital mortality (RR 0.98, 95% CI 0.68–1.41, P = .91), or other secondary outcomes.

Clinically indicated testing is better

The conclusion from these studies is that routine chest radiographs in patients undergoing mechanical ventilation does not improve patient outcomes, and thus, a clinically indicated protocol is preferred.

Furthermore, routine daily radiographs have adverse effects such as more cumulative radiation exposure to the patient⁷ and greater risk of accidental removal of devices (eg, catheters, tubes).⁸ Another concern is a higher risk of hospital-associated infections from bacterial spread from caregivers’ hands.⁹

Finally, daily radiographs increase the use of healthcare resources and expenditures. In a 2011 study, Gershengorn et al¹ estimated that adopting a clinically indicated radiography strategy could save more than $144 million annually in the United States.

The ACR agrees. Appropriateness criteria published by the American College of Radiology (ACR) in 2015¹⁰ recommend against routine daily chest radiographs in the ICU, in keeping with the findings of the critical care community. The ACR recommends an initial radiograph at admission to the ICU. However, follow-up radiographs should be obtained only for specific clinical indications, including a change in the patient’s clinical condition or to check for proper placement of endotracheal or nasogastric or orogastric tubes, pulmonary arterial catheters, central venous catheters, chest tubes, and other life-support devices.

Ultrasonography as an alternative

Ultrasonography is widely available and provides an alternative to chest radiography for detecting significant abnormalities in patients on mechanical ventilation without exposing them to radiation and using relatively fewer resources.

A 2012 meta-analysis (8 studies, 1,048 patients) found that bedside ultrasonography reliably detects pneumothorax.¹¹ It can also provide a rapid diagnosis of the cause of acute respiratory failure such as pneumonia or pulmonary edema.¹² Ultrasonography, with the appropriate expertise, can also confirm the position of an endotracheal tube¹³ or central venous catheter.¹⁴

Arterial blood gas testing has value for managing patients undergoing mechanical ventilation, and it is one of the most commonly performed diagnostic tests in the ICU. It provides reliable information about the patient’s oxygenation and acid-base status. It is commonly requested when changing ventilator settings.

Downsides. Arterial blood gas measurements account for 10% to 20% of the cost incurred during ICU stay.¹⁵ In addition, they require an arterial puncture—an invasive procedure associated with potentially serious complications such as occlusion of the artery, digital embolization leading to digital ischemia, local infection, pseudoaneurysm, hematoma, bleeding, and skin necrosis.

Is daily testing needed?

Guidelines say no. The 2013 American Association for Respiratory Care¹⁶ guidelines suggest that arterial blood gas testing should be based on the clinical assessment of the patient. They recommend blood gas analysis to evaluate the patient’s ventilatory status (reflected by the partial pressure of arterial carbon dioxide [PaCO₂], acid-base status (reflected by pH), arterial oxygenation (partial pressure of arterial oxygen [PaO₂] and oxyhemoglobin saturation), oxygen-carrying capacity, and whether the patient likely has an intrapulmonary shunt. They state that testing is useful to quantify the response to therapeutic or diagnostic interventions such as cardiopulmonary exercise testing, to monitor severity and progression of documented disease, and to assess the adequacy of circulatory response.

Studies agree

The ACR recommendation to test “as clinically indicated” is supported by studies showing that patient outcomes are not inferior for arterial blood gas testing when clinically indicated instead of daily, and that this practice is associated with fewer complications, less resource use, and reduced overall patient care costs.

A 2015 study compared the efficacy and safety of obtaining arterial blood gases based on clinical assessment vs daily in 300 critically ill patients.¹⁷ Overall, fewer samples were obtained per patient in the clinical assessment group than in the daily group (all patients 3.7 vs 5.5; ventilated patients 2.03 vs 6.12; P < .001 for both). In ventilated patients, there was a 60% decrease in arterial blood gas orders without affecting patient outcomes and safety, including a lower risk of complications and overall cost of care.

In another study, Martinez-Balzano et al¹⁸ evaluated the effect of guidelines they developed to optimize the use of arterial blood gas testing in their ICUs. These guidelines encouraged testing of arterial blood gases after an acute respiratory event or for a rational clinical concern, and discouraged testing for routine surveillance, after planned changes of positive end-expiratory pressure or inspired oxygen fraction on mechanical ventilation, for spontaneous breathing trials, or when a disorder was not suspected.

Compared with data collected before implementation, these guidelines reduced the number of arterial blood gas tests by 821.5 per month (41.5%), or approximately 1 test per patient per mechanical-ventilation day for each month (43.1%; P < .001). Appropriately indicated testing rose to 83.4% from a baseline of 67.5% (P = .002). Additionally, this approach was associated with saving 49 liters of blood, reducing ICU costs by $39,432, and freeing up 1,643 staff work hours for other tasks. There were no significant differences in days on mechanical ventilation, severity of illness, or mortality between the 2 periods.¹⁸

Extubation effects. Routine arterial blood gas testing has not been shown to affect extubation decisions in patients on mechanical ventilation. In a study of 83 patients who completed a spontaneous breathing trial (total of 100 trials), Salam et al¹⁹ found arterial blood gas values obtained during the trial did not change the extubation decision in 93% of the cases.

In a study of 54 extubations in 52 patients,²⁰ 65% of the extubations were performed without obtaining an arterial blood gas test after the patient completed a trial of spontaneous breathing. The extubation success rate was 94% for the entire group, and it was the same regardless of whether testing was done (94.7% vs 94.3%, respectively).

Alternatives to arterial blood gases

There are less-invasive means to obtain the information that comes from an arterial blood gas test.

Pulse oximetry is a rapid noninvasive tool that provides continuous assessment of peripheral arterial oxygen saturation as a surrogate marker for tissue arterial oxygenation. However, it cannot measure PaO₂ or PaCO₂.²¹

Transcutaneous carbon dioxide (PTCO₂) monitoring is another continuous noninvasive alternative. The newer PTCO₂ devices are useful in patients with acute respiratory failure and in critically ill patients on vasopressors or vasodilators. Studies have shown good correlation between PTCO₂ and PaCO₂.^22,23

End-tidal carbon dioxide (PetCO₂) is another alternative to estimate PaCO₂. It can also be used to confirm endotracheal tube placement, during transportation, during procedures in which the patient is under conscious sedation, and to monitor the effectiveness of cardiopulmonary resuscitation and return of circulation after cardiac arrest. PetCO₂ measurements are not as accurate as arterial blood gas testing owing to a difference of approximately 2 to 5 mm Hg between PaCO₂ and PetCO₂ in normal lungs due to alveolar dead space. This difference may be much higher depending on the clinical condition and the degree of alveolar dead space.^21,24,25

Venous blood gases, which can be obtained from a peripheral or central venous catheter, are adequate to assess pH and partial pressure of carbon dioxide (PCO₂) in hemodynamically stable patients. Walkey et al²⁶ found that the accuracy of venous blood gas measurement to predict arterial blood gases was 90%. They recommended adjusting the venous pH up by 0.05 and the PCO₂ down by 5 mm Hg to account for the positive bias of venous blood gases. A limitation of this method is that the values are not reliable in patients who are in shock.

These alternatives can be used as a substitute for daily arterial blood gases. However, in certain clinical scenarios, arterial blood gas measurement remains a necessary and useful clinical tool.

TAKE-HOME MESSAGE

Most scientific evidence suggests that chest radiographs and arterial blood gas measurement in patients undergoing mechanical ventilation—and critically ill, in general—are best done when clinically indicated rather than routinely on a daily basis. This will reduce cost and harm to patients that may result from these unnecessary tests and not adversely affect outcomes.

No, they are not required or needed, but daily radiography and arterial blood gas testing are common practice: eg, 60% of intensive care unit (ICU) patients get daily radiographs,¹ even though results provide low diagnostic yield and are unlikely to alter patient management compared with testing only when indicated.

The Choosing Wisely campaign,² a collaborative effort of a number of professional societies, advises against ordering these diagnostic tests daily because routine testing increases risks to patients and burdens the healthcare system. Instead, testing is recommended only in response to a specific clinical question, or when the test results will affect the patient’s treatment.

CHEST RADIOGRAPHS: DAILY VS CLINICALLY INDICATED

Chest radiographs enable practitioners to monitor the position of endotracheal tubes and central venous catheters, evaluate fluid status, follow up on abnormal findings, detect complications of procedures (such as a pneumothorax), and identify otherwise undetected conditions.

And daily chest radiographs often detect abnormalities. A 1991 study by Hall et al³ of 538 chest radiographs in 74 patients on mechanical ventilation reported that 30% of daily routine chest radiographs disclosed a new but minor finding (eg, a small change in endotracheal tube position or a small infiltrate). The new findings were major in 13 (17.6%) of the 74 patients (95% confidence interval [CI] 9%–26%). These included findings that required an immediate diagnostic or therapeutic intervention (eg, endotracheal tube below the tracheal carina, malposition of a catheter, pneumothorax, large pleural effusion).

But most studies say daily radiographs are not needed. In a large prospective study published in 2006, Graat et al⁴ evaluated the clinical value of 2,457 routine chest radiographs in 754 patients in a combined surgical and medical ICU. Daily chest radiographs revealed new or unexpected findings in 5.8% of cases, but only 2.2% warranted a change in therapy. No differences were found between the medical and surgical patients. The authors concluded that daily routine radiographs in ICU patients seldom reveal unexpected, clinically relevant abnormalities, and those findings rarely require urgent intervention.

A 2010 meta-analysis of 8 studies (7,078 patients) by Oba and Zaza⁵ compared on-demand and daily routine strategies of performing chest radiographs. They estimated that eliminating daily routine chest radiographs would not affect death rates in the hospital (odds ratio [OR] 1.02, 95% CI 0.89–1.17, P = .78) or the ICU (OR 0.92, 95% CI 0.76–1.11, P = .4). They also found no significant differences in length of stay or duration of mechanical ventilation. This meta-analysis suggests that routine radiographs can be eliminated without adversely affecting outcomes in ICU patients.

A larger meta-analysis (9 trials, 39,358 radiographs, 9,611 patients) published in 2012 by Ganapathy et al⁶ also found no harm associated with restrictive radiography protocols. These investigators compared a daily chest radiography protocol against a protocol based on clinical indications. The primary outcome was the mortality rate in the ICU; secondary outcomes were the mortality rate in the hospital, the length of stay in the ICU, and duration of mechanical ventilation. They found no differences between routine and restrictive strategies in terms of ICU mortality (risk ratio [RR] 1.04, 95% CI 0.84–1.28, P = .72), hospital mortality (RR 0.98, 95% CI 0.68–1.41, P = .91), or other secondary outcomes.

Clinically indicated testing is better

The conclusion from these studies is that routine chest radiographs in patients undergoing mechanical ventilation does not improve patient outcomes, and thus, a clinically indicated protocol is preferred.

Furthermore, routine daily radiographs have adverse effects such as more cumulative radiation exposure to the patient⁷ and greater risk of accidental removal of devices (eg, catheters, tubes).⁸ Another concern is a higher risk of hospital-associated infections from bacterial spread from caregivers’ hands.⁹

Finally, daily radiographs increase the use of healthcare resources and expenditures. In a 2011 study, Gershengorn et al¹ estimated that adopting a clinically indicated radiography strategy could save more than $144 million annually in the United States.

The ACR agrees. Appropriateness criteria published by the American College of Radiology (ACR) in 2015¹⁰ recommend against routine daily chest radiographs in the ICU, in keeping with the findings of the critical care community. The ACR recommends an initial radiograph at admission to the ICU. However, follow-up radiographs should be obtained only for specific clinical indications, including a change in the patient’s clinical condition or to check for proper placement of endotracheal or nasogastric or orogastric tubes, pulmonary arterial catheters, central venous catheters, chest tubes, and other life-support devices.

Ultrasonography as an alternative

Ultrasonography is widely available and provides an alternative to chest radiography for detecting significant abnormalities in patients on mechanical ventilation without exposing them to radiation and using relatively fewer resources.

A 2012 meta-analysis (8 studies, 1,048 patients) found that bedside ultrasonography reliably detects pneumothorax.¹¹ It can also provide a rapid diagnosis of the cause of acute respiratory failure such as pneumonia or pulmonary edema.¹² Ultrasonography, with the appropriate expertise, can also confirm the position of an endotracheal tube¹³ or central venous catheter.¹⁴

Arterial blood gas testing has value for managing patients undergoing mechanical ventilation, and it is one of the most commonly performed diagnostic tests in the ICU. It provides reliable information about the patient’s oxygenation and acid-base status. It is commonly requested when changing ventilator settings.

Downsides. Arterial blood gas measurements account for 10% to 20% of the cost incurred during ICU stay.¹⁵ In addition, they require an arterial puncture—an invasive procedure associated with potentially serious complications such as occlusion of the artery, digital embolization leading to digital ischemia, local infection, pseudoaneurysm, hematoma, bleeding, and skin necrosis.

Is daily testing needed?

Guidelines say no. The 2013 American Association for Respiratory Care¹⁶ guidelines suggest that arterial blood gas testing should be based on the clinical assessment of the patient. They recommend blood gas analysis to evaluate the patient’s ventilatory status (reflected by the partial pressure of arterial carbon dioxide [PaCO₂], acid-base status (reflected by pH), arterial oxygenation (partial pressure of arterial oxygen [PaO₂] and oxyhemoglobin saturation), oxygen-carrying capacity, and whether the patient likely has an intrapulmonary shunt. They state that testing is useful to quantify the response to therapeutic or diagnostic interventions such as cardiopulmonary exercise testing, to monitor severity and progression of documented disease, and to assess the adequacy of circulatory response.

Studies agree

The ACR recommendation to test “as clinically indicated” is supported by studies showing that patient outcomes are not inferior for arterial blood gas testing when clinically indicated instead of daily, and that this practice is associated with fewer complications, less resource use, and reduced overall patient care costs.

A 2015 study compared the efficacy and safety of obtaining arterial blood gases based on clinical assessment vs daily in 300 critically ill patients.¹⁷ Overall, fewer samples were obtained per patient in the clinical assessment group than in the daily group (all patients 3.7 vs 5.5; ventilated patients 2.03 vs 6.12; P < .001 for both). In ventilated patients, there was a 60% decrease in arterial blood gas orders without affecting patient outcomes and safety, including a lower risk of complications and overall cost of care.

In another study, Martinez-Balzano et al¹⁸ evaluated the effect of guidelines they developed to optimize the use of arterial blood gas testing in their ICUs. These guidelines encouraged testing of arterial blood gases after an acute respiratory event or for a rational clinical concern, and discouraged testing for routine surveillance, after planned changes of positive end-expiratory pressure or inspired oxygen fraction on mechanical ventilation, for spontaneous breathing trials, or when a disorder was not suspected.

Compared with data collected before implementation, these guidelines reduced the number of arterial blood gas tests by 821.5 per month (41.5%), or approximately 1 test per patient per mechanical-ventilation day for each month (43.1%; P < .001). Appropriately indicated testing rose to 83.4% from a baseline of 67.5% (P = .002). Additionally, this approach was associated with saving 49 liters of blood, reducing ICU costs by $39,432, and freeing up 1,643 staff work hours for other tasks. There were no significant differences in days on mechanical ventilation, severity of illness, or mortality between the 2 periods.¹⁸

Extubation effects. Routine arterial blood gas testing has not been shown to affect extubation decisions in patients on mechanical ventilation. In a study of 83 patients who completed a spontaneous breathing trial (total of 100 trials), Salam et al¹⁹ found arterial blood gas values obtained during the trial did not change the extubation decision in 93% of the cases.

In a study of 54 extubations in 52 patients,²⁰ 65% of the extubations were performed without obtaining an arterial blood gas test after the patient completed a trial of spontaneous breathing. The extubation success rate was 94% for the entire group, and it was the same regardless of whether testing was done (94.7% vs 94.3%, respectively).

Alternatives to arterial blood gases

There are less-invasive means to obtain the information that comes from an arterial blood gas test.

Pulse oximetry is a rapid noninvasive tool that provides continuous assessment of peripheral arterial oxygen saturation as a surrogate marker for tissue arterial oxygenation. However, it cannot measure PaO₂ or PaCO₂.²¹

Transcutaneous carbon dioxide (PTCO₂) monitoring is another continuous noninvasive alternative. The newer PTCO₂ devices are useful in patients with acute respiratory failure and in critically ill patients on vasopressors or vasodilators. Studies have shown good correlation between PTCO₂ and PaCO₂.^22,23

End-tidal carbon dioxide (PetCO₂) is another alternative to estimate PaCO₂. It can also be used to confirm endotracheal tube placement, during transportation, during procedures in which the patient is under conscious sedation, and to monitor the effectiveness of cardiopulmonary resuscitation and return of circulation after cardiac arrest. PetCO₂ measurements are not as accurate as arterial blood gas testing owing to a difference of approximately 2 to 5 mm Hg between PaCO₂ and PetCO₂ in normal lungs due to alveolar dead space. This difference may be much higher depending on the clinical condition and the degree of alveolar dead space.^21,24,25

Venous blood gases, which can be obtained from a peripheral or central venous catheter, are adequate to assess pH and partial pressure of carbon dioxide (PCO₂) in hemodynamically stable patients. Walkey et al²⁶ found that the accuracy of venous blood gas measurement to predict arterial blood gases was 90%. They recommended adjusting the venous pH up by 0.05 and the PCO₂ down by 5 mm Hg to account for the positive bias of venous blood gases. A limitation of this method is that the values are not reliable in patients who are in shock.

These alternatives can be used as a substitute for daily arterial blood gases. However, in certain clinical scenarios, arterial blood gas measurement remains a necessary and useful clinical tool.

TAKE-HOME MESSAGE

Most scientific evidence suggests that chest radiographs and arterial blood gas measurement in patients undergoing mechanical ventilation—and critically ill, in general—are best done when clinically indicated rather than routinely on a daily basis. This will reduce cost and harm to patients that may result from these unnecessary tests and not adversely affect outcomes.

An 18-year-old man without any significant medical history was transferred from another hospital for higher-level care after presenting with unremitting chest pain. He had been in his usual state of good health until 7 days before presentation, when he developed mild rhinorrhea and a sore throat, but not a cough. He went to an outpatient clinic, where a rapid test for group A streptococci was done; the result was negative, and he was sent home on supportive measures.

On the day of admission, he awoke with severe, pressure-like, midsternal, nonradiating pain, which he rated 10 on a scale of 10. The pain intensified in the supine position and improved with sitting. A complete review of systems was otherwise negative. He denied having had similar symptoms in the past, as well as sick contacts, recent travel, toxin exposure, illicit substance abuse, pets at home, or tick bites. His family history was negative for cardiac arrhythmias, premature coronary artery disease, thoracic aneurysms or dissection, and infiltrative disorders. His surgical and social histories were unremarkable. He said he had no drug allergies.

On examination, his temperature was 38.1°C (100.6°F), heart rate 101 beats per minute, blood pressure 142/78 mm Hg, respiratory rate 16 breaths per minute, and oxygen saturation 98% on room air. He appeared anxious but was in no acute distress. Neck examination showed no elevation in jugular venous pulsation, bruits, thyromegaly, or lymphadenopathy. Cardiac examination revealed tachycardia without murmurs, rubs, or gallops. Lungs were clear to auscultation. Examination of all 4 extremities found 2+ pulses (on a scale of 0 to 4+) throughout and no cyanosis, clubbing, or edema. Abdominal, neurologic, and dermatologic examinations were unremarkable.

Further blood testing revealed the following:

• Troponin I (3 hours after the first level) 15.5 ng/mL
• B-type natriuretic peptide 200 mg/dL (reference range 0–100 mg/dL)
• C-reactive protein 0.9 mg/dL (reference range 0.0–0.8 mg/dL)
• Erythrocyte sedimentation rate 10 mm/h (reference range < 15 mm/h).

Metabolic and hematologic assessments were unremarkable. A toxicology screen for drugs of abuse was negative. Viral serologic testing was not done.

A chest radiograph showed no acute cardiopulmonary processes.

Given his presenting symptoms, persistent tachycardia, rapidly rising troponin I level, and electrocardiogram showing diffuse ST elevation, he was taken for urgent cardiac catheterization. Coronary angiography revealed no evidence of atherosclerotic disease, acute thrombosis, dissection, or aneurysm. Echocardiography 2 hours after the procedure showed a normal ejection fraction and no regional wall-motion abnormalities or valvular heart disease.

1. Which test should be done next to further evaluate this patient’s chest pain?

• Serum viral serologic testing
• Serum free light chain assay
• Nuclear myocardial perfusion study
• Cardiac magnetic resonance imaging (MRI)
• Endomyocardial biopsy

In this patient without ischemic coronary disease or valvular heart disease, the recent upper respiratory tract prodrome, active positional chest pain, and diffuse electrocardiographic changes raise the possibility of myocarditis with pericardial involvement.

Viral serologic tests

Viral serologic tests are often obtained in the workup of myocarditis as a noninvasive means of detecting an infectious cause.

However, this approach has several problems. First, a positive serologic result is a signal of the peripheral immune response to a pathogen but does not necessarily indicate active myocardial inflammation. Additionally, circulating immunoglobulin G against cardiotropic viruses is commonly found, even in the absence of myocarditis.¹ This is often the result of a high prevalence and exposure to these viruses in the general population. Further, trials have shown no correlation between serologic results and organisms identified by endomyocardial biopsy.²

Thus, serologic testing seems to be of limited utility, reserved for testing for infection with Borrelia burgdorferi (Lyme disease) in endemic areas, hepatitis C virus, human immunodeficiency virus in patients at high risk, Rickettsia conorii, and Rickettsia rickettsii.³

Serum free light chain testing for amyloidosis

Serum free light chain testing is replacing serum and urine protein electrophoresis in the workup of cardiac amyloidosis,⁴ as electrophoresis has poor sensitivity.^4,5

Cardiac amyloidosis often affects older persons, although in rare cases it can affect young patients who carry mutations in the transthyretin gene (ATTR amyloidosis).⁶ This diagnosis is unlikely in our patient, as he has no other affected organ systems (amyloidosis often affects the renal and neurologic systems), normal QRS voltages on electrocardiography (which are often but not always low in amyloidosis), and no left ventricular hypertrophy or diastolic dysfunction on echocardiography (which are often seen in amyloidosis).⁴

Nuclear perfusion imaging for sarcoidosis

Nuclear imaging has a limited role in evaluating myocarditis,³ but positron-emission tomography with fluorine-18 fluorodeoxyglucose has a diagnostic role in sarcoidosis, an immune-mediated cause of myocarditis.⁷

Based on the acuity of the patient’s presentation, preceded by upper respiratory tract symptoms, sarcoidosis is less likely. Sarcoidosis is difficult to diagnose, although when it is the cause of myocarditis, some clues exist, as patients usually present with heart failure symptoms, a second- or third-degree atrioventricular block, or a dilated left ventricle on echocardiography.³ All of these were absent in our patient.

Cardiac MRI

Cardiac MRI has undergone many advances, making it an extremely useful noninvasive test. It has excellent utility as a stand-alone test in diagnosing myocarditis and has synergistic value when combined with endomyocardial biopsy.⁸ It is indicated in hemodynamically stable patients with a clinical suspicion of myocarditis, persistent symptoms, absence of heart failure, and when imaging findings will change management. It is particularly useful to help elucidate a cause and guide tailored therapy.⁹ Therefore, it is a reasonable next step in the diagnostic pathway for this patient.¹⁰

Cardiac MRI also allows for concurrent assessment of scar. In myocardial infarction, the late gadolinium enhancement is subendocardial or transmural. In myocarditis, the pattern differs, being found in the subepicardial lateral free wall (in most patients with parvovirus B19) and mid-myocardial septum (in most patients with herpesvirus 6).^9,11 Cardiac MRI also confers prognostic information for patients with suspected myocarditis.¹²

The Lake Louise criteria⁹ for the diagnosis of myocarditis require 2 of the following:

• Evidence of myocardial edema
• Increased ratio of early gadolinium enhancement between myocardium and skeletal muscle (indicates hyperemia)
• At least 1 focal lesion with nonischemic late gadolinium enhancement (indicates cardiac myocyte injury or scarring).

The Lake Louise criteria may be replaced by T1 and T2 mapping, which was found to be considerably better for diagnosing myocarditis when the 2 were compared.^9,13,14

Endomyocardial biopsy

Endomyocardial biopsy should not be delayed while waiting for cardiac MRI in patients who are hemodynamically unstable or present with life-threatening features (ventricular arrhythmia, left ventricular failure, or resuscitation after sudden cardiac death).^3,10

The indications for endomyocardial biopsy have been highly debated. The 2013 guidelines from the European Society of Cardiology (ESC) recommending endomyocardial biopsy  in all clinically suspected cases of myocarditis have only heightened the controversy.³ The American Heart Association (AHA) guidelines reserve biopsy for patients with suspected myocarditis who have acute or subacute heart failure symptoms or who do not respond to standard medical therapy.¹⁵ Other reasonable indications may include the following: myocarditis with life-threatening ventricular arrhythmias, suspicion of giant cell myocarditis, necrotizing eosinophilic myocarditis, or cardiac sarcoidosis.¹⁶

Endomyocardial biopsy is the only way to make a definitive diagnosis of myocarditis.³ However, given the patchy distribution of myocardial involvement, a negative result does not rule out myocarditis. The diagnostic utility can be improved by increasing the number of samples taken (at least 3 but up to 10), obtaining samples from both ventricles, and using cardiac MRI data to determine which sites to biopsy.^3,13,17,18

Noninvasive testing such as cardiac MRI does not distinguish cell type or etiology (viral vs nonviral).³ Further, endomyocardial biopsy must be performed before immunosuppressive therapy can be safely started.^3,16 At experienced centers, the complication rate is 0% to 0.8%.³ The addition of immunohistochemical testing and viral genomic detection by polymerase chain reaction testing have increased the sensitivity of this technique.¹⁹ Finally, endomyocardial biopsy can help rule out some of the other possibilities in the differential diagnosis for myocarditis, including infiltrative and storage diseases, and possibly cardiac tumors.³

Of additional note, the diffuse ST-segment elevation seen on the patient’s electrocardiogram (Figure 1) is indicative of subepicardial inflammation. Since the distribution involves more than one epicardial coronary territory, this helps to differentiate the changes from those that occur with myocardial infarction.²⁰

Causes of myocarditis are numerous (Table 1),^3,21,22 but viral and postinfectious etiologies remain the most common causes of acute myocarditis.²³

• Parvovirus B19
• Coxsackievirus B
• Adenovirus species
• Human herpesvirus 6
• Staphylococcus aureus
• Corynebacterium diphtheria
• Trypanosoma cruzi
• Influenza H1/N1

INFECTIOUS CAUSES OF MYOCARDITIS

Coxsackievirus B was the agent most often linked to this condition from the 1950s through the 1990s. However, in the last 2 decades, adenovirus species and human herpesvirus 6 have been increasingly encountered, and recently, parvovirus B19 has been credited as the most common culprit,^11,23 at least in the Western world. In developing nations, T cruzi and C diphtheria are the most common offenders^.21

S aureus is a common cause of endocarditis, but it rarely plays a role in myocarditis. When it does, the myocarditis is often the sequela of profound bacteremia. This was much more common before antibiotics were invented.^24,25

Influenza H1/N1 is not among the most common causes of viral myocarditis, but it should be considered during flu season, given its ability to result in fulminant myocarditis.^3,26

TREATMENT FOR MYOCARDITIS

3. Which treatment is the most appropriate at this time?

• Intravenous immunoglobulin
• Interferon beta
• Acyclovir
• Prednisone
• Colchicine

Treatment for myocarditis depends on the cause but always includes supportive care to address the constellation of presenting symptoms. Standard therapies for tachy- or bradyarrhythmias, heart failure, and hemodynamic derangement should be started.

Supportive care

In patients with severe left ventricular dysfunction, an implantable cardiac electronic device, left ventricular assist device, or heart transplant may ultimately be needed. However, if possible these should be deferred for several months to determine response to treatment, since the myocardium can possibly recover.¹⁶

Diuretics, beta-blockers, angiotensin II receptor blockers, angiotensin-converting enzyme inhibitors, and aldosterone antagonists should be given as part of guideline-directed medical therapy for patients with heart failure and reduced ejection fraction.^3,27 However, whether and how the patient should be weaned from these agents after disease recovery are unknown.³

Intravenous immunoglobulin

Intravenous immunoglobulin in high doses has had mixed results. Its efficacy is well documented in children,²¹ but limited supportive data are available in adults.³ As such, recent ESC guidelines do not provide recommendations regarding its use in adults.³

Interferon beta

Interferon beta has shown promise in improving New York Heart Association class and left ventricular ejection fraction.³ This is attributed to its effects on eliminating adenoviral species and enteroviruses. Treatment of enteroviral organisms in particular has been associated with improved 10-year prognosis.³ Interferon beta also has in vitro data showing efficacy at diminishing apoptosis from parvovirus B19.²⁸

Nucleoside analogues

Empiric treatment with nucleoside analogues (acyclovir, ganciclovir, and valacyclovir) has been tried for patients in whom human herpesvirus is suspected as the causative organism, although with unconfirmed effects.³ Consultation with an infectious disease specialist is recommended before starting these agents, and biopsy is often needed beforehand.³

Immunosuppressive agents

Immunosuppressive agents such as prednisone, azathioprine, and cyclosporine can be used in cases of biopsy-proven disease with manifestations of severe heart failure, especially if biopsy results reveal sarcoidosis, giant cell myocarditis, or necrotizing eosinophilic myocarditis. Although the results were neutral in the Myocarditis Treatment Trial,²⁹ the cause of myocarditis in this trial was unknown. Therapy with such agents should be initiated after active infection is ruled out, which also would require a biopsy.

Colchicine

Mechanisms of chest pain in myocarditis include associated pericarditis and coronary artery vasospasm.^3,23 Our patient’s chest pain changed when he changed position, possibly indicating associated pericarditis. In myocarditis with accompanying pericarditis symptoms, colchicine (1–2 mg as an initial dose and then 0.6 mg daily for up to 3 months) can be helpful in alleviating symptoms.^21,30 Thus, starting this agent in a patient who presents with myocarditis in absence of heart failure, arrhythmias, or left ventricular dysfunction is prudent.

Colchicine is used mainly to address the pain associated with pericarditis. For patients who present with pericarditis without myocarditis, nonsteroidal anti-inflammatory drugs (NSAIDs) remain the first-line treatment, with the addition of colchicine leading to faster symptom resolution.³⁰ The benefit of colchicine for isolated myocarditis is not well established, with only limited data showing some clinical effects.³¹

The patient was given colchicine 1.2 mg on the first day and then 0.6 mg daily. Within 2 days, his chest pain had resolved. He did not receive any immunosuppressive agents.

DISCHARGE INSTRUCTIONS

4. Before discharge, this patient should be instructed to do which of the following?

• Take over-the-counter NSAIDs to supplement the effects of colchicine
• Avoid competitive sports and athletics for at least 6 months
• Call to schedule repeat cardiac MRI
• No further instruction is needed

NSAIDs are used by themselves or in combination with colchicine in the treatment of pericarditis, but their use may be associated with worse outcomes in myocarditis.^3,21 Thus, their use is not recommended in most cases.³

Excessive physical activity should be avoided for at least 6 months after the clinical syndrome resolves. This recommendation is included in the most recent ESC guidelines but is based mainly on expert opinion and murine models with coxsackievirus B.³ Periodic reassessment is indicated with exercise stress testing before return to strenuous activity.^3,16,32 Testing should look for exercise tolerance, and exercise electrocardiography also helps to evaluate for clinically relevant arrythmias.

Cardiac MRI can help clarify the prognosis in myocarditis, but the role of repeat testing in guiding therapy is limited.³ Indications for repeat cardiac MRI include presence of 0 or 1 of the Lake Louise criteria (recall that 2 are necessary to make the diagnosis) with recurrence of symptoms and a high suspicion for myocardial inflammation.^3,9 Repeat cardiac MRI was not performed for our patient.

CASE CONCLUDED

The patient was evaluated in the cardiology clinic within 1 week of discharge. At that time, he was in sinus tachycardia with a heart rate of 102 bpm, and he was instructed to avoid any exercise until further notice.

At 6-month follow-up, the sinus tachycardia had resolved. However, because persistent tachycardia had been noted at the first postdischarge visit, and in view of the extent of myocardial involvement, he underwent exercise treadmill testing to evaluate for ventricular arrhythmias. The study did show premature ventricular complexes and 1 ventricular couplet at submaximal exercise levels. As this indicated a higher risk of exercise-induced arrhythmias, he was asked to continue normal activity levels but to abstain from exercise until the next evaluation.

During his 1-year follow-up, a repeat treadmill test showed no ventricular ectopy. Holter monitoring was ordered and showed no premature ventricular complexes, supraventricular arrhythmias, or atrioventricular block within the 48-hour period.

At his 2-year evaluation, he had returned to playing basketball and soccer on weekends and reported no recurrence of his initial symptoms.

KEY POINTS

• 

  Cardiac MRI has emerged as an excellent noninvasive imaging modality for the diagnosis of myocarditis.
• Treatment of myocarditis depends on the cause and severity of the patient’s presentation, spanning the spectrum from conservative care to immunosuppressive agents and even heart failure therapy.
• Excessive physical activity should be avoided for the first 6 months after disease diagnosis and treatment.
• If myocarditis is associated with pericardial involvement, colchicine is the agent of choice, and NSAIDs should be avoided.

Our suggested strategy for approaching myocarditis is shown in Figure 3.

An 18-year-old man without any significant medical history was transferred from another hospital for higher-level care after presenting with unremitting chest pain. He had been in his usual state of good health until 7 days before presentation, when he developed mild rhinorrhea and a sore throat, but not a cough. He went to an outpatient clinic, where a rapid test for group A streptococci was done; the result was negative, and he was sent home on supportive measures.

On the day of admission, he awoke with severe, pressure-like, midsternal, nonradiating pain, which he rated 10 on a scale of 10. The pain intensified in the supine position and improved with sitting. A complete review of systems was otherwise negative. He denied having had similar symptoms in the past, as well as sick contacts, recent travel, toxin exposure, illicit substance abuse, pets at home, or tick bites. His family history was negative for cardiac arrhythmias, premature coronary artery disease, thoracic aneurysms or dissection, and infiltrative disorders. His surgical and social histories were unremarkable. He said he had no drug allergies.

On examination, his temperature was 38.1°C (100.6°F), heart rate 101 beats per minute, blood pressure 142/78 mm Hg, respiratory rate 16 breaths per minute, and oxygen saturation 98% on room air. He appeared anxious but was in no acute distress. Neck examination showed no elevation in jugular venous pulsation, bruits, thyromegaly, or lymphadenopathy. Cardiac examination revealed tachycardia without murmurs, rubs, or gallops. Lungs were clear to auscultation. Examination of all 4 extremities found 2+ pulses (on a scale of 0 to 4+) throughout and no cyanosis, clubbing, or edema. Abdominal, neurologic, and dermatologic examinations were unremarkable.

Further blood testing revealed the following:

• Troponin I (3 hours after the first level) 15.5 ng/mL
• B-type natriuretic peptide 200 mg/dL (reference range 0–100 mg/dL)
• C-reactive protein 0.9 mg/dL (reference range 0.0–0.8 mg/dL)
• Erythrocyte sedimentation rate 10 mm/h (reference range < 15 mm/h).

Metabolic and hematologic assessments were unremarkable. A toxicology screen for drugs of abuse was negative. Viral serologic testing was not done.

A chest radiograph showed no acute cardiopulmonary processes.

Given his presenting symptoms, persistent tachycardia, rapidly rising troponin I level, and electrocardiogram showing diffuse ST elevation, he was taken for urgent cardiac catheterization. Coronary angiography revealed no evidence of atherosclerotic disease, acute thrombosis, dissection, or aneurysm. Echocardiography 2 hours after the procedure showed a normal ejection fraction and no regional wall-motion abnormalities or valvular heart disease.

1. Which test should be done next to further evaluate this patient’s chest pain?

• Serum viral serologic testing
• Serum free light chain assay
• Nuclear myocardial perfusion study
• Cardiac magnetic resonance imaging (MRI)
• Endomyocardial biopsy

In this patient without ischemic coronary disease or valvular heart disease, the recent upper respiratory tract prodrome, active positional chest pain, and diffuse electrocardiographic changes raise the possibility of myocarditis with pericardial involvement.

Viral serologic tests

Viral serologic tests are often obtained in the workup of myocarditis as a noninvasive means of detecting an infectious cause.

However, this approach has several problems. First, a positive serologic result is a signal of the peripheral immune response to a pathogen but does not necessarily indicate active myocardial inflammation. Additionally, circulating immunoglobulin G against cardiotropic viruses is commonly found, even in the absence of myocarditis.¹ This is often the result of a high prevalence and exposure to these viruses in the general population. Further, trials have shown no correlation between serologic results and organisms identified by endomyocardial biopsy.²

Thus, serologic testing seems to be of limited utility, reserved for testing for infection with Borrelia burgdorferi (Lyme disease) in endemic areas, hepatitis C virus, human immunodeficiency virus in patients at high risk, Rickettsia conorii, and Rickettsia rickettsii.³

Serum free light chain testing for amyloidosis

Serum free light chain testing is replacing serum and urine protein electrophoresis in the workup of cardiac amyloidosis,⁴ as electrophoresis has poor sensitivity.^4,5

Cardiac amyloidosis often affects older persons, although in rare cases it can affect young patients who carry mutations in the transthyretin gene (ATTR amyloidosis).⁶ This diagnosis is unlikely in our patient, as he has no other affected organ systems (amyloidosis often affects the renal and neurologic systems), normal QRS voltages on electrocardiography (which are often but not always low in amyloidosis), and no left ventricular hypertrophy or diastolic dysfunction on echocardiography (which are often seen in amyloidosis).⁴

Nuclear perfusion imaging for sarcoidosis

Nuclear imaging has a limited role in evaluating myocarditis,³ but positron-emission tomography with fluorine-18 fluorodeoxyglucose has a diagnostic role in sarcoidosis, an immune-mediated cause of myocarditis.⁷

Based on the acuity of the patient’s presentation, preceded by upper respiratory tract symptoms, sarcoidosis is less likely. Sarcoidosis is difficult to diagnose, although when it is the cause of myocarditis, some clues exist, as patients usually present with heart failure symptoms, a second- or third-degree atrioventricular block, or a dilated left ventricle on echocardiography.³ All of these were absent in our patient.

Cardiac MRI

Cardiac MRI has undergone many advances, making it an extremely useful noninvasive test. It has excellent utility as a stand-alone test in diagnosing myocarditis and has synergistic value when combined with endomyocardial biopsy.⁸ It is indicated in hemodynamically stable patients with a clinical suspicion of myocarditis, persistent symptoms, absence of heart failure, and when imaging findings will change management. It is particularly useful to help elucidate a cause and guide tailored therapy.⁹ Therefore, it is a reasonable next step in the diagnostic pathway for this patient.¹⁰

Cardiac MRI also allows for concurrent assessment of scar. In myocardial infarction, the late gadolinium enhancement is subendocardial or transmural. In myocarditis, the pattern differs, being found in the subepicardial lateral free wall (in most patients with parvovirus B19) and mid-myocardial septum (in most patients with herpesvirus 6).^9,11 Cardiac MRI also confers prognostic information for patients with suspected myocarditis.¹²

The Lake Louise criteria⁹ for the diagnosis of myocarditis require 2 of the following:

• Evidence of myocardial edema
• Increased ratio of early gadolinium enhancement between myocardium and skeletal muscle (indicates hyperemia)
• At least 1 focal lesion with nonischemic late gadolinium enhancement (indicates cardiac myocyte injury or scarring).

The Lake Louise criteria may be replaced by T1 and T2 mapping, which was found to be considerably better for diagnosing myocarditis when the 2 were compared.^9,13,14

Endomyocardial biopsy

Endomyocardial biopsy should not be delayed while waiting for cardiac MRI in patients who are hemodynamically unstable or present with life-threatening features (ventricular arrhythmia, left ventricular failure, or resuscitation after sudden cardiac death).^3,10

The indications for endomyocardial biopsy have been highly debated. The 2013 guidelines from the European Society of Cardiology (ESC) recommending endomyocardial biopsy  in all clinically suspected cases of myocarditis have only heightened the controversy.³ The American Heart Association (AHA) guidelines reserve biopsy for patients with suspected myocarditis who have acute or subacute heart failure symptoms or who do not respond to standard medical therapy.¹⁵ Other reasonable indications may include the following: myocarditis with life-threatening ventricular arrhythmias, suspicion of giant cell myocarditis, necrotizing eosinophilic myocarditis, or cardiac sarcoidosis.¹⁶

Endomyocardial biopsy is the only way to make a definitive diagnosis of myocarditis.³ However, given the patchy distribution of myocardial involvement, a negative result does not rule out myocarditis. The diagnostic utility can be improved by increasing the number of samples taken (at least 3 but up to 10), obtaining samples from both ventricles, and using cardiac MRI data to determine which sites to biopsy.^3,13,17,18

Noninvasive testing such as cardiac MRI does not distinguish cell type or etiology (viral vs nonviral).³ Further, endomyocardial biopsy must be performed before immunosuppressive therapy can be safely started.^3,16 At experienced centers, the complication rate is 0% to 0.8%.³ The addition of immunohistochemical testing and viral genomic detection by polymerase chain reaction testing have increased the sensitivity of this technique.¹⁹ Finally, endomyocardial biopsy can help rule out some of the other possibilities in the differential diagnosis for myocarditis, including infiltrative and storage diseases, and possibly cardiac tumors.³

Of additional note, the diffuse ST-segment elevation seen on the patient’s electrocardiogram (Figure 1) is indicative of subepicardial inflammation. Since the distribution involves more than one epicardial coronary territory, this helps to differentiate the changes from those that occur with myocardial infarction.²⁰

Causes of myocarditis are numerous (Table 1),^3,21,22 but viral and postinfectious etiologies remain the most common causes of acute myocarditis.²³

• Parvovirus B19
• Coxsackievirus B
• Adenovirus species
• Human herpesvirus 6
• Staphylococcus aureus
• Corynebacterium diphtheria
• Trypanosoma cruzi
• Influenza H1/N1

INFECTIOUS CAUSES OF MYOCARDITIS

Coxsackievirus B was the agent most often linked to this condition from the 1950s through the 1990s. However, in the last 2 decades, adenovirus species and human herpesvirus 6 have been increasingly encountered, and recently, parvovirus B19 has been credited as the most common culprit,^11,23 at least in the Western world. In developing nations, T cruzi and C diphtheria are the most common offenders^.21

S aureus is a common cause of endocarditis, but it rarely plays a role in myocarditis. When it does, the myocarditis is often the sequela of profound bacteremia. This was much more common before antibiotics were invented.^24,25

Influenza H1/N1 is not among the most common causes of viral myocarditis, but it should be considered during flu season, given its ability to result in fulminant myocarditis.^3,26

TREATMENT FOR MYOCARDITIS

3. Which treatment is the most appropriate at this time?

• Intravenous immunoglobulin
• Interferon beta
• Acyclovir
• Prednisone
• Colchicine

Treatment for myocarditis depends on the cause but always includes supportive care to address the constellation of presenting symptoms. Standard therapies for tachy- or bradyarrhythmias, heart failure, and hemodynamic derangement should be started.

Supportive care

In patients with severe left ventricular dysfunction, an implantable cardiac electronic device, left ventricular assist device, or heart transplant may ultimately be needed. However, if possible these should be deferred for several months to determine response to treatment, since the myocardium can possibly recover.¹⁶

Diuretics, beta-blockers, angiotensin II receptor blockers, angiotensin-converting enzyme inhibitors, and aldosterone antagonists should be given as part of guideline-directed medical therapy for patients with heart failure and reduced ejection fraction.^3,27 However, whether and how the patient should be weaned from these agents after disease recovery are unknown.³

Intravenous immunoglobulin

Intravenous immunoglobulin in high doses has had mixed results. Its efficacy is well documented in children,²¹ but limited supportive data are available in adults.³ As such, recent ESC guidelines do not provide recommendations regarding its use in adults.³

Interferon beta

Interferon beta has shown promise in improving New York Heart Association class and left ventricular ejection fraction.³ This is attributed to its effects on eliminating adenoviral species and enteroviruses. Treatment of enteroviral organisms in particular has been associated with improved 10-year prognosis.³ Interferon beta also has in vitro data showing efficacy at diminishing apoptosis from parvovirus B19.²⁸

Nucleoside analogues

Empiric treatment with nucleoside analogues (acyclovir, ganciclovir, and valacyclovir) has been tried for patients in whom human herpesvirus is suspected as the causative organism, although with unconfirmed effects.³ Consultation with an infectious disease specialist is recommended before starting these agents, and biopsy is often needed beforehand.³

Immunosuppressive agents

Immunosuppressive agents such as prednisone, azathioprine, and cyclosporine can be used in cases of biopsy-proven disease with manifestations of severe heart failure, especially if biopsy results reveal sarcoidosis, giant cell myocarditis, or necrotizing eosinophilic myocarditis. Although the results were neutral in the Myocarditis Treatment Trial,²⁹ the cause of myocarditis in this trial was unknown. Therapy with such agents should be initiated after active infection is ruled out, which also would require a biopsy.

Colchicine

Mechanisms of chest pain in myocarditis include associated pericarditis and coronary artery vasospasm.^3,23 Our patient’s chest pain changed when he changed position, possibly indicating associated pericarditis. In myocarditis with accompanying pericarditis symptoms, colchicine (1–2 mg as an initial dose and then 0.6 mg daily for up to 3 months) can be helpful in alleviating symptoms.^21,30 Thus, starting this agent in a patient who presents with myocarditis in absence of heart failure, arrhythmias, or left ventricular dysfunction is prudent.

Colchicine is used mainly to address the pain associated with pericarditis. For patients who present with pericarditis without myocarditis, nonsteroidal anti-inflammatory drugs (NSAIDs) remain the first-line treatment, with the addition of colchicine leading to faster symptom resolution.³⁰ The benefit of colchicine for isolated myocarditis is not well established, with only limited data showing some clinical effects.³¹

The patient was given colchicine 1.2 mg on the first day and then 0.6 mg daily. Within 2 days, his chest pain had resolved. He did not receive any immunosuppressive agents.

DISCHARGE INSTRUCTIONS

4. Before discharge, this patient should be instructed to do which of the following?

• Take over-the-counter NSAIDs to supplement the effects of colchicine
• Avoid competitive sports and athletics for at least 6 months
• Call to schedule repeat cardiac MRI
• No further instruction is needed

NSAIDs are used by themselves or in combination with colchicine in the treatment of pericarditis, but their use may be associated with worse outcomes in myocarditis.^3,21 Thus, their use is not recommended in most cases.³

Excessive physical activity should be avoided for at least 6 months after the clinical syndrome resolves. This recommendation is included in the most recent ESC guidelines but is based mainly on expert opinion and murine models with coxsackievirus B.³ Periodic reassessment is indicated with exercise stress testing before return to strenuous activity.^3,16,32 Testing should look for exercise tolerance, and exercise electrocardiography also helps to evaluate for clinically relevant arrythmias.

Cardiac MRI can help clarify the prognosis in myocarditis, but the role of repeat testing in guiding therapy is limited.³ Indications for repeat cardiac MRI include presence of 0 or 1 of the Lake Louise criteria (recall that 2 are necessary to make the diagnosis) with recurrence of symptoms and a high suspicion for myocardial inflammation.^3,9 Repeat cardiac MRI was not performed for our patient.

CASE CONCLUDED

The patient was evaluated in the cardiology clinic within 1 week of discharge. At that time, he was in sinus tachycardia with a heart rate of 102 bpm, and he was instructed to avoid any exercise until further notice.

At 6-month follow-up, the sinus tachycardia had resolved. However, because persistent tachycardia had been noted at the first postdischarge visit, and in view of the extent of myocardial involvement, he underwent exercise treadmill testing to evaluate for ventricular arrhythmias. The study did show premature ventricular complexes and 1 ventricular couplet at submaximal exercise levels. As this indicated a higher risk of exercise-induced arrhythmias, he was asked to continue normal activity levels but to abstain from exercise until the next evaluation.

During his 1-year follow-up, a repeat treadmill test showed no ventricular ectopy. Holter monitoring was ordered and showed no premature ventricular complexes, supraventricular arrhythmias, or atrioventricular block within the 48-hour period.

At his 2-year evaluation, he had returned to playing basketball and soccer on weekends and reported no recurrence of his initial symptoms.

KEY POINTS

• 

  Cardiac MRI has emerged as an excellent noninvasive imaging modality for the diagnosis of myocarditis.
• Treatment of myocarditis depends on the cause and severity of the patient’s presentation, spanning the spectrum from conservative care to immunosuppressive agents and even heart failure therapy.
• Excessive physical activity should be avoided for the first 6 months after disease diagnosis and treatment.
• If myocarditis is associated with pericardial involvement, colchicine is the agent of choice, and NSAIDs should be avoided.

Our suggested strategy for approaching myocarditis is shown in Figure 3.

An 18-year-old man without any significant medical history was transferred from another hospital for higher-level care after presenting with unremitting chest pain. He had been in his usual state of good health until 7 days before presentation, when he developed mild rhinorrhea and a sore throat, but not a cough. He went to an outpatient clinic, where a rapid test for group A streptococci was done; the result was negative, and he was sent home on supportive measures.

On the day of admission, he awoke with severe, pressure-like, midsternal, nonradiating pain, which he rated 10 on a scale of 10. The pain intensified in the supine position and improved with sitting. A complete review of systems was otherwise negative. He denied having had similar symptoms in the past, as well as sick contacts, recent travel, toxin exposure, illicit substance abuse, pets at home, or tick bites. His family history was negative for cardiac arrhythmias, premature coronary artery disease, thoracic aneurysms or dissection, and infiltrative disorders. His surgical and social histories were unremarkable. He said he had no drug allergies.

On examination, his temperature was 38.1°C (100.6°F), heart rate 101 beats per minute, blood pressure 142/78 mm Hg, respiratory rate 16 breaths per minute, and oxygen saturation 98% on room air. He appeared anxious but was in no acute distress. Neck examination showed no elevation in jugular venous pulsation, bruits, thyromegaly, or lymphadenopathy. Cardiac examination revealed tachycardia without murmurs, rubs, or gallops. Lungs were clear to auscultation. Examination of all 4 extremities found 2+ pulses (on a scale of 0 to 4+) throughout and no cyanosis, clubbing, or edema. Abdominal, neurologic, and dermatologic examinations were unremarkable.

Further blood testing revealed the following:

• Troponin I (3 hours after the first level) 15.5 ng/mL
• B-type natriuretic peptide 200 mg/dL (reference range 0–100 mg/dL)
• C-reactive protein 0.9 mg/dL (reference range 0.0–0.8 mg/dL)
• Erythrocyte sedimentation rate 10 mm/h (reference range < 15 mm/h).

Metabolic and hematologic assessments were unremarkable. A toxicology screen for drugs of abuse was negative. Viral serologic testing was not done.

A chest radiograph showed no acute cardiopulmonary processes.

Given his presenting symptoms, persistent tachycardia, rapidly rising troponin I level, and electrocardiogram showing diffuse ST elevation, he was taken for urgent cardiac catheterization. Coronary angiography revealed no evidence of atherosclerotic disease, acute thrombosis, dissection, or aneurysm. Echocardiography 2 hours after the procedure showed a normal ejection fraction and no regional wall-motion abnormalities or valvular heart disease.

1. Which test should be done next to further evaluate this patient’s chest pain?

• Serum viral serologic testing
• Serum free light chain assay
• Nuclear myocardial perfusion study
• Cardiac magnetic resonance imaging (MRI)
• Endomyocardial biopsy

In this patient without ischemic coronary disease or valvular heart disease, the recent upper respiratory tract prodrome, active positional chest pain, and diffuse electrocardiographic changes raise the possibility of myocarditis with pericardial involvement.

Viral serologic tests

Viral serologic tests are often obtained in the workup of myocarditis as a noninvasive means of detecting an infectious cause.

However, this approach has several problems. First, a positive serologic result is a signal of the peripheral immune response to a pathogen but does not necessarily indicate active myocardial inflammation. Additionally, circulating immunoglobulin G against cardiotropic viruses is commonly found, even in the absence of myocarditis.¹ This is often the result of a high prevalence and exposure to these viruses in the general population. Further, trials have shown no correlation between serologic results and organisms identified by endomyocardial biopsy.²

Thus, serologic testing seems to be of limited utility, reserved for testing for infection with Borrelia burgdorferi (Lyme disease) in endemic areas, hepatitis C virus, human immunodeficiency virus in patients at high risk, Rickettsia conorii, and Rickettsia rickettsii.³

Serum free light chain testing for amyloidosis

Serum free light chain testing is replacing serum and urine protein electrophoresis in the workup of cardiac amyloidosis,⁴ as electrophoresis has poor sensitivity.^4,5

Cardiac amyloidosis often affects older persons, although in rare cases it can affect young patients who carry mutations in the transthyretin gene (ATTR amyloidosis).⁶ This diagnosis is unlikely in our patient, as he has no other affected organ systems (amyloidosis often affects the renal and neurologic systems), normal QRS voltages on electrocardiography (which are often but not always low in amyloidosis), and no left ventricular hypertrophy or diastolic dysfunction on echocardiography (which are often seen in amyloidosis).⁴

Nuclear perfusion imaging for sarcoidosis

Nuclear imaging has a limited role in evaluating myocarditis,³ but positron-emission tomography with fluorine-18 fluorodeoxyglucose has a diagnostic role in sarcoidosis, an immune-mediated cause of myocarditis.⁷

Based on the acuity of the patient’s presentation, preceded by upper respiratory tract symptoms, sarcoidosis is less likely. Sarcoidosis is difficult to diagnose, although when it is the cause of myocarditis, some clues exist, as patients usually present with heart failure symptoms, a second- or third-degree atrioventricular block, or a dilated left ventricle on echocardiography.³ All of these were absent in our patient.

Cardiac MRI

Cardiac MRI has undergone many advances, making it an extremely useful noninvasive test. It has excellent utility as a stand-alone test in diagnosing myocarditis and has synergistic value when combined with endomyocardial biopsy.⁸ It is indicated in hemodynamically stable patients with a clinical suspicion of myocarditis, persistent symptoms, absence of heart failure, and when imaging findings will change management. It is particularly useful to help elucidate a cause and guide tailored therapy.⁹ Therefore, it is a reasonable next step in the diagnostic pathway for this patient.¹⁰

Cardiac MRI also allows for concurrent assessment of scar. In myocardial infarction, the late gadolinium enhancement is subendocardial or transmural. In myocarditis, the pattern differs, being found in the subepicardial lateral free wall (in most patients with parvovirus B19) and mid-myocardial septum (in most patients with herpesvirus 6).^9,11 Cardiac MRI also confers prognostic information for patients with suspected myocarditis.¹²

The Lake Louise criteria⁹ for the diagnosis of myocarditis require 2 of the following:

• Evidence of myocardial edema
• Increased ratio of early gadolinium enhancement between myocardium and skeletal muscle (indicates hyperemia)
• At least 1 focal lesion with nonischemic late gadolinium enhancement (indicates cardiac myocyte injury or scarring).

The Lake Louise criteria may be replaced by T1 and T2 mapping, which was found to be considerably better for diagnosing myocarditis when the 2 were compared.^9,13,14

Endomyocardial biopsy

Endomyocardial biopsy should not be delayed while waiting for cardiac MRI in patients who are hemodynamically unstable or present with life-threatening features (ventricular arrhythmia, left ventricular failure, or resuscitation after sudden cardiac death).^3,10

The indications for endomyocardial biopsy have been highly debated. The 2013 guidelines from the European Society of Cardiology (ESC) recommending endomyocardial biopsy  in all clinically suspected cases of myocarditis have only heightened the controversy.³ The American Heart Association (AHA) guidelines reserve biopsy for patients with suspected myocarditis who have acute or subacute heart failure symptoms or who do not respond to standard medical therapy.¹⁵ Other reasonable indications may include the following: myocarditis with life-threatening ventricular arrhythmias, suspicion of giant cell myocarditis, necrotizing eosinophilic myocarditis, or cardiac sarcoidosis.¹⁶

Endomyocardial biopsy is the only way to make a definitive diagnosis of myocarditis.³ However, given the patchy distribution of myocardial involvement, a negative result does not rule out myocarditis. The diagnostic utility can be improved by increasing the number of samples taken (at least 3 but up to 10), obtaining samples from both ventricles, and using cardiac MRI data to determine which sites to biopsy.^3,13,17,18

Noninvasive testing such as cardiac MRI does not distinguish cell type or etiology (viral vs nonviral).³ Further, endomyocardial biopsy must be performed before immunosuppressive therapy can be safely started.^3,16 At experienced centers, the complication rate is 0% to 0.8%.³ The addition of immunohistochemical testing and viral genomic detection by polymerase chain reaction testing have increased the sensitivity of this technique.¹⁹ Finally, endomyocardial biopsy can help rule out some of the other possibilities in the differential diagnosis for myocarditis, including infiltrative and storage diseases, and possibly cardiac tumors.³

Of additional note, the diffuse ST-segment elevation seen on the patient’s electrocardiogram (Figure 1) is indicative of subepicardial inflammation. Since the distribution involves more than one epicardial coronary territory, this helps to differentiate the changes from those that occur with myocardial infarction.²⁰

Causes of myocarditis are numerous (Table 1),^3,21,22 but viral and postinfectious etiologies remain the most common causes of acute myocarditis.²³

• Parvovirus B19
• Coxsackievirus B
• Adenovirus species
• Human herpesvirus 6
• Staphylococcus aureus
• Corynebacterium diphtheria
• Trypanosoma cruzi
• Influenza H1/N1

INFECTIOUS CAUSES OF MYOCARDITIS

Coxsackievirus B was the agent most often linked to this condition from the 1950s through the 1990s. However, in the last 2 decades, adenovirus species and human herpesvirus 6 have been increasingly encountered, and recently, parvovirus B19 has been credited as the most common culprit,^11,23 at least in the Western world. In developing nations, T cruzi and C diphtheria are the most common offenders^.21

S aureus is a common cause of endocarditis, but it rarely plays a role in myocarditis. When it does, the myocarditis is often the sequela of profound bacteremia. This was much more common before antibiotics were invented.^24,25

Influenza H1/N1 is not among the most common causes of viral myocarditis, but it should be considered during flu season, given its ability to result in fulminant myocarditis.^3,26

TREATMENT FOR MYOCARDITIS

3. Which treatment is the most appropriate at this time?

• Intravenous immunoglobulin
• Interferon beta
• Acyclovir
• Prednisone
• Colchicine

Treatment for myocarditis depends on the cause but always includes supportive care to address the constellation of presenting symptoms. Standard therapies for tachy- or bradyarrhythmias, heart failure, and hemodynamic derangement should be started.

Supportive care

In patients with severe left ventricular dysfunction, an implantable cardiac electronic device, left ventricular assist device, or heart transplant may ultimately be needed. However, if possible these should be deferred for several months to determine response to treatment, since the myocardium can possibly recover.¹⁶

Diuretics, beta-blockers, angiotensin II receptor blockers, angiotensin-converting enzyme inhibitors, and aldosterone antagonists should be given as part of guideline-directed medical therapy for patients with heart failure and reduced ejection fraction.^3,27 However, whether and how the patient should be weaned from these agents after disease recovery are unknown.³

Intravenous immunoglobulin

Intravenous immunoglobulin in high doses has had mixed results. Its efficacy is well documented in children,²¹ but limited supportive data are available in adults.³ As such, recent ESC guidelines do not provide recommendations regarding its use in adults.³

Interferon beta

Interferon beta has shown promise in improving New York Heart Association class and left ventricular ejection fraction.³ This is attributed to its effects on eliminating adenoviral species and enteroviruses. Treatment of enteroviral organisms in particular has been associated with improved 10-year prognosis.³ Interferon beta also has in vitro data showing efficacy at diminishing apoptosis from parvovirus B19.²⁸

Nucleoside analogues

Empiric treatment with nucleoside analogues (acyclovir, ganciclovir, and valacyclovir) has been tried for patients in whom human herpesvirus is suspected as the causative organism, although with unconfirmed effects.³ Consultation with an infectious disease specialist is recommended before starting these agents, and biopsy is often needed beforehand.³

Immunosuppressive agents

Immunosuppressive agents such as prednisone, azathioprine, and cyclosporine can be used in cases of biopsy-proven disease with manifestations of severe heart failure, especially if biopsy results reveal sarcoidosis, giant cell myocarditis, or necrotizing eosinophilic myocarditis. Although the results were neutral in the Myocarditis Treatment Trial,²⁹ the cause of myocarditis in this trial was unknown. Therapy with such agents should be initiated after active infection is ruled out, which also would require a biopsy.

Colchicine

Mechanisms of chest pain in myocarditis include associated pericarditis and coronary artery vasospasm.^3,23 Our patient’s chest pain changed when he changed position, possibly indicating associated pericarditis. In myocarditis with accompanying pericarditis symptoms, colchicine (1–2 mg as an initial dose and then 0.6 mg daily for up to 3 months) can be helpful in alleviating symptoms.^21,30 Thus, starting this agent in a patient who presents with myocarditis in absence of heart failure, arrhythmias, or left ventricular dysfunction is prudent.

Colchicine is used mainly to address the pain associated with pericarditis. For patients who present with pericarditis without myocarditis, nonsteroidal anti-inflammatory drugs (NSAIDs) remain the first-line treatment, with the addition of colchicine leading to faster symptom resolution.³⁰ The benefit of colchicine for isolated myocarditis is not well established, with only limited data showing some clinical effects.³¹

The patient was given colchicine 1.2 mg on the first day and then 0.6 mg daily. Within 2 days, his chest pain had resolved. He did not receive any immunosuppressive agents.

DISCHARGE INSTRUCTIONS

4. Before discharge, this patient should be instructed to do which of the following?

• Take over-the-counter NSAIDs to supplement the effects of colchicine
• Avoid competitive sports and athletics for at least 6 months
• Call to schedule repeat cardiac MRI
• No further instruction is needed

NSAIDs are used by themselves or in combination with colchicine in the treatment of pericarditis, but their use may be associated with worse outcomes in myocarditis.^3,21 Thus, their use is not recommended in most cases.³

Excessive physical activity should be avoided for at least 6 months after the clinical syndrome resolves. This recommendation is included in the most recent ESC guidelines but is based mainly on expert opinion and murine models with coxsackievirus B.³ Periodic reassessment is indicated with exercise stress testing before return to strenuous activity.^3,16,32 Testing should look for exercise tolerance, and exercise electrocardiography also helps to evaluate for clinically relevant arrythmias.

Cardiac MRI can help clarify the prognosis in myocarditis, but the role of repeat testing in guiding therapy is limited.³ Indications for repeat cardiac MRI include presence of 0 or 1 of the Lake Louise criteria (recall that 2 are necessary to make the diagnosis) with recurrence of symptoms and a high suspicion for myocardial inflammation.^3,9 Repeat cardiac MRI was not performed for our patient.

CASE CONCLUDED

The patient was evaluated in the cardiology clinic within 1 week of discharge. At that time, he was in sinus tachycardia with a heart rate of 102 bpm, and he was instructed to avoid any exercise until further notice.

At 6-month follow-up, the sinus tachycardia had resolved. However, because persistent tachycardia had been noted at the first postdischarge visit, and in view of the extent of myocardial involvement, he underwent exercise treadmill testing to evaluate for ventricular arrhythmias. The study did show premature ventricular complexes and 1 ventricular couplet at submaximal exercise levels. As this indicated a higher risk of exercise-induced arrhythmias, he was asked to continue normal activity levels but to abstain from exercise until the next evaluation.

During his 1-year follow-up, a repeat treadmill test showed no ventricular ectopy. Holter monitoring was ordered and showed no premature ventricular complexes, supraventricular arrhythmias, or atrioventricular block within the 48-hour period.

At his 2-year evaluation, he had returned to playing basketball and soccer on weekends and reported no recurrence of his initial symptoms.

KEY POINTS

• 

  Cardiac MRI has emerged as an excellent noninvasive imaging modality for the diagnosis of myocarditis.
• Treatment of myocarditis depends on the cause and severity of the patient’s presentation, spanning the spectrum from conservative care to immunosuppressive agents and even heart failure therapy.
• Excessive physical activity should be avoided for the first 6 months after disease diagnosis and treatment.
• If myocarditis is associated with pericardial involvement, colchicine is the agent of choice, and NSAIDs should be avoided.

Our suggested strategy for approaching myocarditis is shown in Figure 3.

Biologics improved coronary inflammation as well as psoriasis symptoms, according to data from the perivascular fat attenuation index in 134 adults identified using coronary CT angiography.

Oxford Academic Cardiovascular CT Core Lab and Lab of Inflammation and Cardiometabolic Diseases at NHLBI

“The perivascular fat attenuation index [FAI] is a [CT]-based, novel, noninvasive imaging technique that allows for direct visualization and quantification of coronary inflammation using differential mapping of attenuation gradients in pericoronary fat,” wrote Youssef A. Elnabawi, MD, of the National Heart, Lung, and Blood Institute and colleagues. Biologics have been associated with reduced noncalcified coronary plaques in psoriasis patients, which suggests possible reduction in coronary inflammation as well.

In a study published in JAMA Cardiology, the researchers analyzed data from 134 adults with moderate to severe psoriasis who received no biologic therapy for at least 3 months before starting the study. Of these, 52 chose not to receive biologics, and served as controls while being treated with topical or light therapies. The participants are part of the Psoriasis Atherosclerosis Cardiometabolic Initiative, an ongoing, prospective cohort study. The average age of the patients was 51 years, and 63% were male.

The 82 patients given biologics received anti–tumor necrosis factor–alpha, anti–interleukin-12/23, or anti-IL-17 for 1 year. Overall, patients on biologics showed a significant decrease in FAI from a median of –71.22 Hounsfield units (HU) at baseline to a median of –76.06 at 1 year. These patients also showed significant improvement in Psoriasis Area and Severity Index scores, from a median of 7.7 at baseline to a median of 3.2 at 1 year. The control patients not on biologics showed no significant changes in FAI, with a median of –71.98 HU at baseline and –72.66 HU at 1 year.

The changes were consistent among the various biologics used, and The median FAI for patients on anti–tumor necrosis factor–alpha changed from –71.25 at baseline to –75.49 at 1 year; median FAI for both IL-12/23 and anti-IL-17 treatment groups changed from –71.18 HU at baseline to –76.92 at 1 year.

In addition, only patients treated with biologics showed a significant reduction in median C-reactive protein levels from baseline (2.2 mg/L vs. 1.3 mg/L). The changes in FAI were not associated with the presence of coronary plaques, the researchers noted.

The study findings were limited by several factors, including the observational design, small size, and lack of data on cardiovascular endpoints. “Future studies will be needed to explore whether the residual CV risk detected by perivascular FAI can be attenuated using targeted anti-inflammatory interventions,” they wrote.

However, the results suggest that biologics impact coronary vasculature at the microenvironmental level, and that FAI can be a noninvasive, cost-effective way to stratify patients at increased risk for cardiovascular disease, the researchers noted.


“We believe that the strength of perivascular FAI in risk stratifying patients with increased coronary inflammation will allow for better identification of patients at increased risk of future myocardial events that are not captured by traditional CV risk factors,” they wrote.

The study was funded by the National Institutes of Health, several research foundations, Elsevier, Colgate-Palmolive, and Genentech. Dr. Elnabawi had no financial conflicts to disclose; several coauthors reported relationships with multiple companies. One coauthor disclosed a pending and licensed patent to a novel tool for cardiovascular risk stratification based on the CT attenuation of perivascular tissue (OxScore) and a pending and licensed patent to perivascular texture index.

SOURCE: Elnabawi YA et al. JAMA Cardiol. 2019 Jul 31. doi: 10.1001/jamacardio.2019.2589.

Biologics improved coronary inflammation as well as psoriasis symptoms, according to data from the perivascular fat attenuation index in 134 adults identified using coronary CT angiography.

Oxford Academic Cardiovascular CT Core Lab and Lab of Inflammation and Cardiometabolic Diseases at NHLBI

“The perivascular fat attenuation index [FAI] is a [CT]-based, novel, noninvasive imaging technique that allows for direct visualization and quantification of coronary inflammation using differential mapping of attenuation gradients in pericoronary fat,” wrote Youssef A. Elnabawi, MD, of the National Heart, Lung, and Blood Institute and colleagues. Biologics have been associated with reduced noncalcified coronary plaques in psoriasis patients, which suggests possible reduction in coronary inflammation as well.

In a study published in JAMA Cardiology, the researchers analyzed data from 134 adults with moderate to severe psoriasis who received no biologic therapy for at least 3 months before starting the study. Of these, 52 chose not to receive biologics, and served as controls while being treated with topical or light therapies. The participants are part of the Psoriasis Atherosclerosis Cardiometabolic Initiative, an ongoing, prospective cohort study. The average age of the patients was 51 years, and 63% were male.

The 82 patients given biologics received anti–tumor necrosis factor–alpha, anti–interleukin-12/23, or anti-IL-17 for 1 year. Overall, patients on biologics showed a significant decrease in FAI from a median of –71.22 Hounsfield units (HU) at baseline to a median of –76.06 at 1 year. These patients also showed significant improvement in Psoriasis Area and Severity Index scores, from a median of 7.7 at baseline to a median of 3.2 at 1 year. The control patients not on biologics showed no significant changes in FAI, with a median of –71.98 HU at baseline and –72.66 HU at 1 year.

The changes were consistent among the various biologics used, and The median FAI for patients on anti–tumor necrosis factor–alpha changed from –71.25 at baseline to –75.49 at 1 year; median FAI for both IL-12/23 and anti-IL-17 treatment groups changed from –71.18 HU at baseline to –76.92 at 1 year.

In addition, only patients treated with biologics showed a significant reduction in median C-reactive protein levels from baseline (2.2 mg/L vs. 1.3 mg/L). The changes in FAI were not associated with the presence of coronary plaques, the researchers noted.

The study findings were limited by several factors, including the observational design, small size, and lack of data on cardiovascular endpoints. “Future studies will be needed to explore whether the residual CV risk detected by perivascular FAI can be attenuated using targeted anti-inflammatory interventions,” they wrote.

However, the results suggest that biologics impact coronary vasculature at the microenvironmental level, and that FAI can be a noninvasive, cost-effective way to stratify patients at increased risk for cardiovascular disease, the researchers noted.


“We believe that the strength of perivascular FAI in risk stratifying patients with increased coronary inflammation will allow for better identification of patients at increased risk of future myocardial events that are not captured by traditional CV risk factors,” they wrote.

The study was funded by the National Institutes of Health, several research foundations, Elsevier, Colgate-Palmolive, and Genentech. Dr. Elnabawi had no financial conflicts to disclose; several coauthors reported relationships with multiple companies. One coauthor disclosed a pending and licensed patent to a novel tool for cardiovascular risk stratification based on the CT attenuation of perivascular tissue (OxScore) and a pending and licensed patent to perivascular texture index.

SOURCE: Elnabawi YA et al. JAMA Cardiol. 2019 Jul 31. doi: 10.1001/jamacardio.2019.2589.

Biologics improved coronary inflammation as well as psoriasis symptoms, according to data from the perivascular fat attenuation index in 134 adults identified using coronary CT angiography.

Oxford Academic Cardiovascular CT Core Lab and Lab of Inflammation and Cardiometabolic Diseases at NHLBI

“The perivascular fat attenuation index [FAI] is a [CT]-based, novel, noninvasive imaging technique that allows for direct visualization and quantification of coronary inflammation using differential mapping of attenuation gradients in pericoronary fat,” wrote Youssef A. Elnabawi, MD, of the National Heart, Lung, and Blood Institute and colleagues. Biologics have been associated with reduced noncalcified coronary plaques in psoriasis patients, which suggests possible reduction in coronary inflammation as well.

In a study published in JAMA Cardiology, the researchers analyzed data from 134 adults with moderate to severe psoriasis who received no biologic therapy for at least 3 months before starting the study. Of these, 52 chose not to receive biologics, and served as controls while being treated with topical or light therapies. The participants are part of the Psoriasis Atherosclerosis Cardiometabolic Initiative, an ongoing, prospective cohort study. The average age of the patients was 51 years, and 63% were male.

The 82 patients given biologics received anti–tumor necrosis factor–alpha, anti–interleukin-12/23, or anti-IL-17 for 1 year. Overall, patients on biologics showed a significant decrease in FAI from a median of –71.22 Hounsfield units (HU) at baseline to a median of –76.06 at 1 year. These patients also showed significant improvement in Psoriasis Area and Severity Index scores, from a median of 7.7 at baseline to a median of 3.2 at 1 year. The control patients not on biologics showed no significant changes in FAI, with a median of –71.98 HU at baseline and –72.66 HU at 1 year.

The changes were consistent among the various biologics used, and The median FAI for patients on anti–tumor necrosis factor–alpha changed from –71.25 at baseline to –75.49 at 1 year; median FAI for both IL-12/23 and anti-IL-17 treatment groups changed from –71.18 HU at baseline to –76.92 at 1 year.

In addition, only patients treated with biologics showed a significant reduction in median C-reactive protein levels from baseline (2.2 mg/L vs. 1.3 mg/L). The changes in FAI were not associated with the presence of coronary plaques, the researchers noted.

The study findings were limited by several factors, including the observational design, small size, and lack of data on cardiovascular endpoints. “Future studies will be needed to explore whether the residual CV risk detected by perivascular FAI can be attenuated using targeted anti-inflammatory interventions,” they wrote.

However, the results suggest that biologics impact coronary vasculature at the microenvironmental level, and that FAI can be a noninvasive, cost-effective way to stratify patients at increased risk for cardiovascular disease, the researchers noted.


“We believe that the strength of perivascular FAI in risk stratifying patients with increased coronary inflammation will allow for better identification of patients at increased risk of future myocardial events that are not captured by traditional CV risk factors,” they wrote.

The study was funded by the National Institutes of Health, several research foundations, Elsevier, Colgate-Palmolive, and Genentech. Dr. Elnabawi had no financial conflicts to disclose; several coauthors reported relationships with multiple companies. One coauthor disclosed a pending and licensed patent to a novel tool for cardiovascular risk stratification based on the CT attenuation of perivascular tissue (OxScore) and a pending and licensed patent to perivascular texture index.

SOURCE: Elnabawi YA et al. JAMA Cardiol. 2019 Jul 31. doi: 10.1001/jamacardio.2019.2589.