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Cardiac procedures tied to higher cancer risk in adult congenital heart disease
NEW ORLEANS – The greater the lifetime number of cardiac procedures entailing exposure to low-dose ionizing radiation, the higher the associated cancer risk in adults with congenital heart disease, Sarah Cohen, MD, reported at the American Heart Association scientific sessions.
This finding takes on added clinical import because the use of such procedures has increased markedly in patients with adult congenital heart disease, added Dr. Cohen of McGill University in Montreal.
She presented analyses of nearly 25,000 patients in the Quebec congenital heart disease database who were ages 18-64 with no history of cancer in January 1995; 602 of them were diagnosed with cancer during follow-up through 2009. Each was matched to four cancer-free controls in the database on the basis of age, sex, congenital heart disease severity, and calendar year.
Patients with a lifetime total of four or five cardiac procedures involving exposure to low-dose ionizing radiation were 1.7-fold more likely to be diagnosed with cancer during follow-up than were those with a history of no such procedures or just one. With a lifetime history of six or more of the procedures, the relative risk climbed to 2.2-fold.
Nearly 90% of the malignancies were genitourinary, respiratory, digestive, breast, or hematologic cancers.
Dr. Cohen and her coinvestigators also conducted a cohort study comparing the relative risk of developing cancer in 1,781 high-exposure Quebec adults in the database who had a lifetime history of four or more cardiac procedures involving radiation exposure to more than 20,000 others with a history of not more than one such procedure. The high-exposure group had a 3.3-fold greater rate of malignancy during follow-up.
In a separate study, Dr. Cohen’s McGill colleagues analyzed the Quebec database and documented the sharp rise over time in low-dose ionizing radiation cardiac procedures, including catheter-based diagnostic procedures, structural heart interventions, nuclear procedures, coronary interventions, computed tomography scans of the chest, coronary interventions, and insertion or repair of pacemakers and implantable cardioverter-defibrillators. In 1990, the rate was 18.5 such procedures per 1,000 patients per year. By 2005, it had nearly tripled to 51.9 per 1,000 per year. The age at first procedure dropped from 5 years to 9 months (Circulation 2016 Jan 5;133[1]:12-20).
Dr. Cohen reported having no financial disclosures.
NEW ORLEANS – The greater the lifetime number of cardiac procedures entailing exposure to low-dose ionizing radiation, the higher the associated cancer risk in adults with congenital heart disease, Sarah Cohen, MD, reported at the American Heart Association scientific sessions.
This finding takes on added clinical import because the use of such procedures has increased markedly in patients with adult congenital heart disease, added Dr. Cohen of McGill University in Montreal.
She presented analyses of nearly 25,000 patients in the Quebec congenital heart disease database who were ages 18-64 with no history of cancer in January 1995; 602 of them were diagnosed with cancer during follow-up through 2009. Each was matched to four cancer-free controls in the database on the basis of age, sex, congenital heart disease severity, and calendar year.
Patients with a lifetime total of four or five cardiac procedures involving exposure to low-dose ionizing radiation were 1.7-fold more likely to be diagnosed with cancer during follow-up than were those with a history of no such procedures or just one. With a lifetime history of six or more of the procedures, the relative risk climbed to 2.2-fold.
Nearly 90% of the malignancies were genitourinary, respiratory, digestive, breast, or hematologic cancers.
Dr. Cohen and her coinvestigators also conducted a cohort study comparing the relative risk of developing cancer in 1,781 high-exposure Quebec adults in the database who had a lifetime history of four or more cardiac procedures involving radiation exposure to more than 20,000 others with a history of not more than one such procedure. The high-exposure group had a 3.3-fold greater rate of malignancy during follow-up.
In a separate study, Dr. Cohen’s McGill colleagues analyzed the Quebec database and documented the sharp rise over time in low-dose ionizing radiation cardiac procedures, including catheter-based diagnostic procedures, structural heart interventions, nuclear procedures, coronary interventions, computed tomography scans of the chest, coronary interventions, and insertion or repair of pacemakers and implantable cardioverter-defibrillators. In 1990, the rate was 18.5 such procedures per 1,000 patients per year. By 2005, it had nearly tripled to 51.9 per 1,000 per year. The age at first procedure dropped from 5 years to 9 months (Circulation 2016 Jan 5;133[1]:12-20).
Dr. Cohen reported having no financial disclosures.
NEW ORLEANS – The greater the lifetime number of cardiac procedures entailing exposure to low-dose ionizing radiation, the higher the associated cancer risk in adults with congenital heart disease, Sarah Cohen, MD, reported at the American Heart Association scientific sessions.
This finding takes on added clinical import because the use of such procedures has increased markedly in patients with adult congenital heart disease, added Dr. Cohen of McGill University in Montreal.
She presented analyses of nearly 25,000 patients in the Quebec congenital heart disease database who were ages 18-64 with no history of cancer in January 1995; 602 of them were diagnosed with cancer during follow-up through 2009. Each was matched to four cancer-free controls in the database on the basis of age, sex, congenital heart disease severity, and calendar year.
Patients with a lifetime total of four or five cardiac procedures involving exposure to low-dose ionizing radiation were 1.7-fold more likely to be diagnosed with cancer during follow-up than were those with a history of no such procedures or just one. With a lifetime history of six or more of the procedures, the relative risk climbed to 2.2-fold.
Nearly 90% of the malignancies were genitourinary, respiratory, digestive, breast, or hematologic cancers.
Dr. Cohen and her coinvestigators also conducted a cohort study comparing the relative risk of developing cancer in 1,781 high-exposure Quebec adults in the database who had a lifetime history of four or more cardiac procedures involving radiation exposure to more than 20,000 others with a history of not more than one such procedure. The high-exposure group had a 3.3-fold greater rate of malignancy during follow-up.
In a separate study, Dr. Cohen’s McGill colleagues analyzed the Quebec database and documented the sharp rise over time in low-dose ionizing radiation cardiac procedures, including catheter-based diagnostic procedures, structural heart interventions, nuclear procedures, coronary interventions, computed tomography scans of the chest, coronary interventions, and insertion or repair of pacemakers and implantable cardioverter-defibrillators. In 1990, the rate was 18.5 such procedures per 1,000 patients per year. By 2005, it had nearly tripled to 51.9 per 1,000 per year. The age at first procedure dropped from 5 years to 9 months (Circulation 2016 Jan 5;133[1]:12-20).
Dr. Cohen reported having no financial disclosures.
AT THE AHA SCIENTIFIC SESSIONS
Key clinical point:
Major finding: Adults with congenital heart disease who had a lifetime history of six or more cardiac procedures involving exposure to low-dose ionizing radiation were 2.2-fold more likely to develop cancer during follow-up than were those with not more than one such procedure.
Data source: This nested, case-control study included 602 adults with congenital heart disease who developed cancer, each matched to four controls who did not.
Disclosures: The study presenter reported having no financial disclosures.
Echocardiography can benefit use of stented bovine graft for MVR in infants
Mitral valve replacement in infants and young children is complicated because appropriately sized prostheses are difficult to come by and these patients need replacements later on as they continue to grow – thus the high rates of reintervention and death. Pediatric cardiac surgery specialists at Boston Children’s Hospital are among the few that have used stented jugular vein grafts in these patients, and they have reported on a refinement of their technique that uses echocardiography before and after graft placement to obtain valuable measurements for sizing and implanting a prosthesis and for identifying patients at risk of complications.
Lindsay R. Freud, MD, and her associates reported in the January 2017 issue of the Journal of Thoracic and Cardiovascular Surgery on pre- and postoperative echocardiograms of 24 patients who had mitral valve replacement (MVR) with the Melody stent-mounted, valved bovine jugular vein graft (Medtronic) (J Thorac Cardiovasc Surg. 2017;153:153-60). The device, which is approved for transcatheter pulmonary valve replacement, was adapted for implantation into the mitral position, an indication that is not yet Food and Drug Administration approved. “With the increasing use of the Melody valve in the mitral position in infants and young children, we sought to provide a framework for both pre- and early postoperative echocardiographic assessment,” Dr. Freud and her coauthors said.
“The potential dimensions often had normal z scores with fair correlation with intraoperative Melody dilation,” the investigators said. They also found that a ratio of the narrowest subaortic region in systole to the actual MV dimension (SubA:MV) less than 0.5 was associated with postoperative left ventricular outflow tract obstruction (LVOTO), which occurred in four patients. The median age of the study group was 8.5 months.
“Postoperatively, mitral gradients substantially improved, with low values relative to the effective orifice area of the Melody valve,” Dr. Freud and her associates said. None of the patients had significant regurgitation or perivalvar leak.
In early reports of the Melody valve in infants and small children, the surgeons determined the size of the replacement valve during the operation itself. Despite encouraging early results, reports of complications such as LVOTO soon followed. The Children’s Hospital Boston researchers undertook the study to determine if echocardiography before surgery would help to identify the correct valve size for expansion and predict which patients would be at risk for LVOTO.
“The preoperative SubA:MV ratio may help assess the risk for postoperative LVOTO, which is an important complication,” Dr. Freud and coauthors said. The presence of LVOTO preoperatively was also a risk factor, but only one of eight patients with an atrioventricular canal defect developed LVOTO. In patients with a SubA:MV ratio less than 0.5, preoperative LVOTO, or any other anatomic risk factor, surgeons should consider options to prevent LVOTO, Dr. Freud and her associates said. Those alternatives include more aggressive resection of stent material, atrial displacement of the valve, or less aggressive distal expansion of the valve.
Postoperative echocardiography enabled Dr. Freud and her coauthors to outline baseline values for the Melody valve in the mitral position by maximum intraoperative balloon diameter, ranging from 1 cm to 1.8 cm in 0.2-cm steps, and depending on five measurements at each step: peak and mean gradients, peak velocity, effective orifice area, and indexed effective orifice area.
“Validation of candidacy for Melody MVR and noninvasive assessment among larger series of patient will be necessary as greater experience with the Melody valve evolves,” Dr. Freud and her associates concluded.
Coauthor Sitaram Emani, MD, has filed a patent for an expandable valve through Boston Children’s Hospital. Dr. Freud and her other coauthors had no financial relationships to disclose.
The Melody valve is an “appealing solution” for MVR in infants and small children, Patrick Myers, MD, of Geneva University Hospitals said in his invited commentary (J Thorac Cardiovasc Surg. 2017;153:151-2) “This contribution brings further data to support Melody MVR,” he said of the report by Dr. Freud and her colleagues.
However, Dr. Myers noted that beyond the Boston Children’s Hospital experience, only two other reports of the Melody valve in the mitral position in children exist. “There are several outstanding technical issues that need to be investigated for the use of the Melody valve in the mitral position,” he said. Among those issues is the length of the stent itself – 28 mm, which can lead to LVOTO after placement “in a diminutive ventricle.” The fact that “only” four patients in the study group developed LVOTO after Melody MVR is “reassuring with regard to this theoretic limitation,” Dr. Myers said. “And the echocardiographic ratio of the narrowest subaortic region in systole to the actual mitral valve dimension could be of use in deciding when to be more aggressive in preventing LVOTO,” he said.
Dr. Myers also said that this report answered some questions about the durability of a venous valve under systemic pressures, but added, “Further echocardiographic and clinical follow-up data in this very challenging population are required,” he said.
Dr. Myers had no financial relationships to disclose.
The Melody valve is an “appealing solution” for MVR in infants and small children, Patrick Myers, MD, of Geneva University Hospitals said in his invited commentary (J Thorac Cardiovasc Surg. 2017;153:151-2) “This contribution brings further data to support Melody MVR,” he said of the report by Dr. Freud and her colleagues.
However, Dr. Myers noted that beyond the Boston Children’s Hospital experience, only two other reports of the Melody valve in the mitral position in children exist. “There are several outstanding technical issues that need to be investigated for the use of the Melody valve in the mitral position,” he said. Among those issues is the length of the stent itself – 28 mm, which can lead to LVOTO after placement “in a diminutive ventricle.” The fact that “only” four patients in the study group developed LVOTO after Melody MVR is “reassuring with regard to this theoretic limitation,” Dr. Myers said. “And the echocardiographic ratio of the narrowest subaortic region in systole to the actual mitral valve dimension could be of use in deciding when to be more aggressive in preventing LVOTO,” he said.
Dr. Myers also said that this report answered some questions about the durability of a venous valve under systemic pressures, but added, “Further echocardiographic and clinical follow-up data in this very challenging population are required,” he said.
Dr. Myers had no financial relationships to disclose.
The Melody valve is an “appealing solution” for MVR in infants and small children, Patrick Myers, MD, of Geneva University Hospitals said in his invited commentary (J Thorac Cardiovasc Surg. 2017;153:151-2) “This contribution brings further data to support Melody MVR,” he said of the report by Dr. Freud and her colleagues.
However, Dr. Myers noted that beyond the Boston Children’s Hospital experience, only two other reports of the Melody valve in the mitral position in children exist. “There are several outstanding technical issues that need to be investigated for the use of the Melody valve in the mitral position,” he said. Among those issues is the length of the stent itself – 28 mm, which can lead to LVOTO after placement “in a diminutive ventricle.” The fact that “only” four patients in the study group developed LVOTO after Melody MVR is “reassuring with regard to this theoretic limitation,” Dr. Myers said. “And the echocardiographic ratio of the narrowest subaortic region in systole to the actual mitral valve dimension could be of use in deciding when to be more aggressive in preventing LVOTO,” he said.
Dr. Myers also said that this report answered some questions about the durability of a venous valve under systemic pressures, but added, “Further echocardiographic and clinical follow-up data in this very challenging population are required,” he said.
Dr. Myers had no financial relationships to disclose.
Mitral valve replacement in infants and young children is complicated because appropriately sized prostheses are difficult to come by and these patients need replacements later on as they continue to grow – thus the high rates of reintervention and death. Pediatric cardiac surgery specialists at Boston Children’s Hospital are among the few that have used stented jugular vein grafts in these patients, and they have reported on a refinement of their technique that uses echocardiography before and after graft placement to obtain valuable measurements for sizing and implanting a prosthesis and for identifying patients at risk of complications.
Lindsay R. Freud, MD, and her associates reported in the January 2017 issue of the Journal of Thoracic and Cardiovascular Surgery on pre- and postoperative echocardiograms of 24 patients who had mitral valve replacement (MVR) with the Melody stent-mounted, valved bovine jugular vein graft (Medtronic) (J Thorac Cardiovasc Surg. 2017;153:153-60). The device, which is approved for transcatheter pulmonary valve replacement, was adapted for implantation into the mitral position, an indication that is not yet Food and Drug Administration approved. “With the increasing use of the Melody valve in the mitral position in infants and young children, we sought to provide a framework for both pre- and early postoperative echocardiographic assessment,” Dr. Freud and her coauthors said.
“The potential dimensions often had normal z scores with fair correlation with intraoperative Melody dilation,” the investigators said. They also found that a ratio of the narrowest subaortic region in systole to the actual MV dimension (SubA:MV) less than 0.5 was associated with postoperative left ventricular outflow tract obstruction (LVOTO), which occurred in four patients. The median age of the study group was 8.5 months.
“Postoperatively, mitral gradients substantially improved, with low values relative to the effective orifice area of the Melody valve,” Dr. Freud and her associates said. None of the patients had significant regurgitation or perivalvar leak.
In early reports of the Melody valve in infants and small children, the surgeons determined the size of the replacement valve during the operation itself. Despite encouraging early results, reports of complications such as LVOTO soon followed. The Children’s Hospital Boston researchers undertook the study to determine if echocardiography before surgery would help to identify the correct valve size for expansion and predict which patients would be at risk for LVOTO.
“The preoperative SubA:MV ratio may help assess the risk for postoperative LVOTO, which is an important complication,” Dr. Freud and coauthors said. The presence of LVOTO preoperatively was also a risk factor, but only one of eight patients with an atrioventricular canal defect developed LVOTO. In patients with a SubA:MV ratio less than 0.5, preoperative LVOTO, or any other anatomic risk factor, surgeons should consider options to prevent LVOTO, Dr. Freud and her associates said. Those alternatives include more aggressive resection of stent material, atrial displacement of the valve, or less aggressive distal expansion of the valve.
Postoperative echocardiography enabled Dr. Freud and her coauthors to outline baseline values for the Melody valve in the mitral position by maximum intraoperative balloon diameter, ranging from 1 cm to 1.8 cm in 0.2-cm steps, and depending on five measurements at each step: peak and mean gradients, peak velocity, effective orifice area, and indexed effective orifice area.
“Validation of candidacy for Melody MVR and noninvasive assessment among larger series of patient will be necessary as greater experience with the Melody valve evolves,” Dr. Freud and her associates concluded.
Coauthor Sitaram Emani, MD, has filed a patent for an expandable valve through Boston Children’s Hospital. Dr. Freud and her other coauthors had no financial relationships to disclose.
Mitral valve replacement in infants and young children is complicated because appropriately sized prostheses are difficult to come by and these patients need replacements later on as they continue to grow – thus the high rates of reintervention and death. Pediatric cardiac surgery specialists at Boston Children’s Hospital are among the few that have used stented jugular vein grafts in these patients, and they have reported on a refinement of their technique that uses echocardiography before and after graft placement to obtain valuable measurements for sizing and implanting a prosthesis and for identifying patients at risk of complications.
Lindsay R. Freud, MD, and her associates reported in the January 2017 issue of the Journal of Thoracic and Cardiovascular Surgery on pre- and postoperative echocardiograms of 24 patients who had mitral valve replacement (MVR) with the Melody stent-mounted, valved bovine jugular vein graft (Medtronic) (J Thorac Cardiovasc Surg. 2017;153:153-60). The device, which is approved for transcatheter pulmonary valve replacement, was adapted for implantation into the mitral position, an indication that is not yet Food and Drug Administration approved. “With the increasing use of the Melody valve in the mitral position in infants and young children, we sought to provide a framework for both pre- and early postoperative echocardiographic assessment,” Dr. Freud and her coauthors said.
“The potential dimensions often had normal z scores with fair correlation with intraoperative Melody dilation,” the investigators said. They also found that a ratio of the narrowest subaortic region in systole to the actual MV dimension (SubA:MV) less than 0.5 was associated with postoperative left ventricular outflow tract obstruction (LVOTO), which occurred in four patients. The median age of the study group was 8.5 months.
“Postoperatively, mitral gradients substantially improved, with low values relative to the effective orifice area of the Melody valve,” Dr. Freud and her associates said. None of the patients had significant regurgitation or perivalvar leak.
In early reports of the Melody valve in infants and small children, the surgeons determined the size of the replacement valve during the operation itself. Despite encouraging early results, reports of complications such as LVOTO soon followed. The Children’s Hospital Boston researchers undertook the study to determine if echocardiography before surgery would help to identify the correct valve size for expansion and predict which patients would be at risk for LVOTO.
“The preoperative SubA:MV ratio may help assess the risk for postoperative LVOTO, which is an important complication,” Dr. Freud and coauthors said. The presence of LVOTO preoperatively was also a risk factor, but only one of eight patients with an atrioventricular canal defect developed LVOTO. In patients with a SubA:MV ratio less than 0.5, preoperative LVOTO, or any other anatomic risk factor, surgeons should consider options to prevent LVOTO, Dr. Freud and her associates said. Those alternatives include more aggressive resection of stent material, atrial displacement of the valve, or less aggressive distal expansion of the valve.
Postoperative echocardiography enabled Dr. Freud and her coauthors to outline baseline values for the Melody valve in the mitral position by maximum intraoperative balloon diameter, ranging from 1 cm to 1.8 cm in 0.2-cm steps, and depending on five measurements at each step: peak and mean gradients, peak velocity, effective orifice area, and indexed effective orifice area.
“Validation of candidacy for Melody MVR and noninvasive assessment among larger series of patient will be necessary as greater experience with the Melody valve evolves,” Dr. Freud and her associates concluded.
Coauthor Sitaram Emani, MD, has filed a patent for an expandable valve through Boston Children’s Hospital. Dr. Freud and her other coauthors had no financial relationships to disclose.
FROM JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY
Key clinical point: Preoperative echocardiography may help guide placement of modified stented jugular vein grafts in infants and small children with hypoplastic mitral and aortic valves.
Major finding: Echocardiography showed that a ratio of the narrowest subaortic region in systole to the actual mitral valve dimension of less than 0.5 was associated with postoperative left ventricular outflow tract obstruction.
Data source: Single-center, retrospective review of 24 patients who underwent mitral valve replacement with modified stented jugular vein grafts from March 2010 to March 2015.
Disclosures: Coauthor Sitaram Emani, MD, has filed a patent for an expandable valve through Boston Children’s Hospital. Dr. Freud and her other coauthors had no financial relationships to disclose.
Hybrid procedures may be better option for LVOTO in lower-weight neonates
Little outcomes data have been published comparing hybrid and Norwood stage 1 procedures for newborns with critical left ventricular outflow tract obstruction (LVOTO), but a prospective analysis of more than 500 operations over 9 years reported that while the Norwood has better survival rates overall, hybrid procedures may improve survival in low-birth-weight newborns.
“Although lower birth weight was identified as an important risk factor for death for the entire cohort, the detrimental impact of low birth weight was mitigated, to some degree, for patients who underwent a hybrid procedure,” said Travis Wilder, MD, of the Congenital Heart Surgeons’ Society (CHSS) Data Center, and his coauthors. They reported their findings in the January 2017 issue of the Journal of Thoracic and Cardiovascular Surgery (153:163-72).
Norwood operations involve major surgical reconstruction along with exposure to cardiopulmonary bypass (CPB), with either deep hypothermic circulatory arrest (DHCA) or regional cerebral perfusion, during aortic arch reconstruction. Previous reports have linked CPB to postoperative hemodynamic instability, complications, and death (Ann Thorac Surg. 2009 Jun;87:1885-92). “In addition, the early physiological stress imposed on neonates after Norwood operations raises concerns regarding adverse neurodevelopment,” Dr. Wilder and his coauthors wrote.
Dr. Wilder and his coauthors pointed out that the hybrid procedure has emerged to avoid CPB and DHCA or regional cerebral perfusion and the potential resulting physiologic instability. “In this light, hybrid palliation may be perceived as a lower-risk alternative to Norwood operations, especially for patients considered at high risk for mortality,” the researchers said. Despite that perception, the actual survival “remains incompletely defined,” they said.
The overall average 4-year unadjusted survival for the entire study population was 65%, but those who had the NW-RVPA procedure had significantly improved survival (73%) vs. both the NW-BT (61%) and the hybrid groups (60%).
Those who had the hybrid procedure were older at stage 1 (12 days vs. 8 and 6 days, respectively for NW-BT and NW-RVPA) and had lower birth weight (2.9 kg vs. 3.2 kg and 3.15 kg, respectively). Hybrid patients also had a higher prevalence of baseline right ventricle dysfunction, were more likely to have baseline tricuspid valve regurgitation, and had a lower prevalence of aortic and mitral valve atresia.
For all patients, birth weight of 2.0-2.5 kg had a strong association with poor survival, Dr. Wilder and his coauthors reported, but the drop-off in survival for low-birth-weight neonates was greater in the Norwood group than in the hybrid group. “This finding suggests that hybrid procedures may offer a modest survival advantage over NW-RVPA at birth weight less than or equal to 2.0 kg and over NW-BT at birth weight less than or equal to 3.0 kg,” the researchers said.
Dr. Wilder and his coauthors had no financial relationships to disclose.
While the study by Dr. Wilder and his coauthors may have drawn an accurate conclusion about low-birth-weight newborns possibly benefiting from a hybrid procedure for hypoplastic left heart syndrome, the number of patients in each strategy was small, Carlos M. Mery, MD, MPH, of Texas Children’s Hospital/Baylor College of Medicine, Houston, said in his invited commentary (J Thorac Cardiovasc Surg. 2017 Jan;153:173-4).
Dr. Mery noted other limitations of the study, namely the heterogeneity of procedures by participating center. “Of the 20 centers, only 11 performed any hybrid procedures, and 1 center accounted for 42% of all hybrid procedures performed,” he said. “Because centers may be associated with possibly unaccounted risk factors and different learning curves, the conclusions may not be easily generalizable.”
The conclusion that newborns of lower birth weight may benefit from the hybrid procedure helps to bring clarity for which patients may benefit from a specific procedure, Dr. Mery said. “We seem to be getting closer to the ultimate goal of being able to offer each individual patient the management strategy that will lead to the best possible outcome, not only for quantity but also for quality of life,” Dr. Mery said.
Dr. Mery had no financial relationships to disclose.
While the study by Dr. Wilder and his coauthors may have drawn an accurate conclusion about low-birth-weight newborns possibly benefiting from a hybrid procedure for hypoplastic left heart syndrome, the number of patients in each strategy was small, Carlos M. Mery, MD, MPH, of Texas Children’s Hospital/Baylor College of Medicine, Houston, said in his invited commentary (J Thorac Cardiovasc Surg. 2017 Jan;153:173-4).
Dr. Mery noted other limitations of the study, namely the heterogeneity of procedures by participating center. “Of the 20 centers, only 11 performed any hybrid procedures, and 1 center accounted for 42% of all hybrid procedures performed,” he said. “Because centers may be associated with possibly unaccounted risk factors and different learning curves, the conclusions may not be easily generalizable.”
The conclusion that newborns of lower birth weight may benefit from the hybrid procedure helps to bring clarity for which patients may benefit from a specific procedure, Dr. Mery said. “We seem to be getting closer to the ultimate goal of being able to offer each individual patient the management strategy that will lead to the best possible outcome, not only for quantity but also for quality of life,” Dr. Mery said.
Dr. Mery had no financial relationships to disclose.
While the study by Dr. Wilder and his coauthors may have drawn an accurate conclusion about low-birth-weight newborns possibly benefiting from a hybrid procedure for hypoplastic left heart syndrome, the number of patients in each strategy was small, Carlos M. Mery, MD, MPH, of Texas Children’s Hospital/Baylor College of Medicine, Houston, said in his invited commentary (J Thorac Cardiovasc Surg. 2017 Jan;153:173-4).
Dr. Mery noted other limitations of the study, namely the heterogeneity of procedures by participating center. “Of the 20 centers, only 11 performed any hybrid procedures, and 1 center accounted for 42% of all hybrid procedures performed,” he said. “Because centers may be associated with possibly unaccounted risk factors and different learning curves, the conclusions may not be easily generalizable.”
The conclusion that newborns of lower birth weight may benefit from the hybrid procedure helps to bring clarity for which patients may benefit from a specific procedure, Dr. Mery said. “We seem to be getting closer to the ultimate goal of being able to offer each individual patient the management strategy that will lead to the best possible outcome, not only for quantity but also for quality of life,” Dr. Mery said.
Dr. Mery had no financial relationships to disclose.
Little outcomes data have been published comparing hybrid and Norwood stage 1 procedures for newborns with critical left ventricular outflow tract obstruction (LVOTO), but a prospective analysis of more than 500 operations over 9 years reported that while the Norwood has better survival rates overall, hybrid procedures may improve survival in low-birth-weight newborns.
“Although lower birth weight was identified as an important risk factor for death for the entire cohort, the detrimental impact of low birth weight was mitigated, to some degree, for patients who underwent a hybrid procedure,” said Travis Wilder, MD, of the Congenital Heart Surgeons’ Society (CHSS) Data Center, and his coauthors. They reported their findings in the January 2017 issue of the Journal of Thoracic and Cardiovascular Surgery (153:163-72).
Norwood operations involve major surgical reconstruction along with exposure to cardiopulmonary bypass (CPB), with either deep hypothermic circulatory arrest (DHCA) or regional cerebral perfusion, during aortic arch reconstruction. Previous reports have linked CPB to postoperative hemodynamic instability, complications, and death (Ann Thorac Surg. 2009 Jun;87:1885-92). “In addition, the early physiological stress imposed on neonates after Norwood operations raises concerns regarding adverse neurodevelopment,” Dr. Wilder and his coauthors wrote.
Dr. Wilder and his coauthors pointed out that the hybrid procedure has emerged to avoid CPB and DHCA or regional cerebral perfusion and the potential resulting physiologic instability. “In this light, hybrid palliation may be perceived as a lower-risk alternative to Norwood operations, especially for patients considered at high risk for mortality,” the researchers said. Despite that perception, the actual survival “remains incompletely defined,” they said.
The overall average 4-year unadjusted survival for the entire study population was 65%, but those who had the NW-RVPA procedure had significantly improved survival (73%) vs. both the NW-BT (61%) and the hybrid groups (60%).
Those who had the hybrid procedure were older at stage 1 (12 days vs. 8 and 6 days, respectively for NW-BT and NW-RVPA) and had lower birth weight (2.9 kg vs. 3.2 kg and 3.15 kg, respectively). Hybrid patients also had a higher prevalence of baseline right ventricle dysfunction, were more likely to have baseline tricuspid valve regurgitation, and had a lower prevalence of aortic and mitral valve atresia.
For all patients, birth weight of 2.0-2.5 kg had a strong association with poor survival, Dr. Wilder and his coauthors reported, but the drop-off in survival for low-birth-weight neonates was greater in the Norwood group than in the hybrid group. “This finding suggests that hybrid procedures may offer a modest survival advantage over NW-RVPA at birth weight less than or equal to 2.0 kg and over NW-BT at birth weight less than or equal to 3.0 kg,” the researchers said.
Dr. Wilder and his coauthors had no financial relationships to disclose.
Little outcomes data have been published comparing hybrid and Norwood stage 1 procedures for newborns with critical left ventricular outflow tract obstruction (LVOTO), but a prospective analysis of more than 500 operations over 9 years reported that while the Norwood has better survival rates overall, hybrid procedures may improve survival in low-birth-weight newborns.
“Although lower birth weight was identified as an important risk factor for death for the entire cohort, the detrimental impact of low birth weight was mitigated, to some degree, for patients who underwent a hybrid procedure,” said Travis Wilder, MD, of the Congenital Heart Surgeons’ Society (CHSS) Data Center, and his coauthors. They reported their findings in the January 2017 issue of the Journal of Thoracic and Cardiovascular Surgery (153:163-72).
Norwood operations involve major surgical reconstruction along with exposure to cardiopulmonary bypass (CPB), with either deep hypothermic circulatory arrest (DHCA) or regional cerebral perfusion, during aortic arch reconstruction. Previous reports have linked CPB to postoperative hemodynamic instability, complications, and death (Ann Thorac Surg. 2009 Jun;87:1885-92). “In addition, the early physiological stress imposed on neonates after Norwood operations raises concerns regarding adverse neurodevelopment,” Dr. Wilder and his coauthors wrote.
Dr. Wilder and his coauthors pointed out that the hybrid procedure has emerged to avoid CPB and DHCA or regional cerebral perfusion and the potential resulting physiologic instability. “In this light, hybrid palliation may be perceived as a lower-risk alternative to Norwood operations, especially for patients considered at high risk for mortality,” the researchers said. Despite that perception, the actual survival “remains incompletely defined,” they said.
The overall average 4-year unadjusted survival for the entire study population was 65%, but those who had the NW-RVPA procedure had significantly improved survival (73%) vs. both the NW-BT (61%) and the hybrid groups (60%).
Those who had the hybrid procedure were older at stage 1 (12 days vs. 8 and 6 days, respectively for NW-BT and NW-RVPA) and had lower birth weight (2.9 kg vs. 3.2 kg and 3.15 kg, respectively). Hybrid patients also had a higher prevalence of baseline right ventricle dysfunction, were more likely to have baseline tricuspid valve regurgitation, and had a lower prevalence of aortic and mitral valve atresia.
For all patients, birth weight of 2.0-2.5 kg had a strong association with poor survival, Dr. Wilder and his coauthors reported, but the drop-off in survival for low-birth-weight neonates was greater in the Norwood group than in the hybrid group. “This finding suggests that hybrid procedures may offer a modest survival advantage over NW-RVPA at birth weight less than or equal to 2.0 kg and over NW-BT at birth weight less than or equal to 3.0 kg,” the researchers said.
Dr. Wilder and his coauthors had no financial relationships to disclose.
FROM THE JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY
Key clinical point: Norwood procedures have the best survival rates for neonates with critical left ventricular outflow tract obstruction, but hybrid procedures may improve survival for those with lower birth weight.
Major finding: Risk-adjusted 4-year survival was 76% for the Norwood operation with a right ventricle–to-pulmonary artery conduit, 61% for Norwood with a modified Blalock-Taussig shunt and 60% for the hybrid procedure.
Data source: Prospective observational cohort study of 564 neonates admitted to 21 Congenital Heart Surgeons’ Society institutions from 2005 to 2014.
Disclosures: Dr. Wilder and his coauthors had no financial relationships to disclose.
Cancer risk six times higher in children with congenital heart defects
NEW ORLEANS – Children with congenital heart defects have a five- to sixfold increased risk of developing pediatric cancer, Matthew Oster, MD, reported at the American Heart Association scientific sessions.
“The absolute risk is small, but it’s still a five- to sixfold risk compared to the general pediatric population, and it does warrant monitoring and a high index of suspicion in our children with congenital heart defects,” said Dr. Oster of Children’s Healthcare of Atlanta. 
The increased cancer risk in adults with congenital heart defects has recently been the focus of research attention. However, little is known about the risk of cancer during the childhood of patients with congenital heart defects.
This was the impetus for Dr. Oster’s nationwide retrospective study of 6.1 million children and adolescents continuously enrolled in private, employer-sponsored health insurance plans during 2009-2015. The data came from the Truven Health MarketScan administrative database.
Children with Down syndrome were excluded from the study because their condition is known to be associated with increased rates of both congenital heart defects and pediatric cancers.
Among 88,493 individuals under age 18 with a diagnosed congenital heart defect, the incidence of any neoplasm diagnosed at least 30 days after diagnosis of the heart defect was 3.91/1,000, compared with 0.79/1,000 in more than 6 million children and adolescents without congenital heart disease.
Thus, children with a congenital heart defect were at a 4.9-fold increased risk for developing a childhood cancer. The risk for bone tumors was 11.2-fold greater than in the general pediatric population, and their neuroblastoma risk was 9.8-fold greater. Their risks of lymphoma and leukemia were increased 5.2- and 2.8-fold, respectively. Of note, they had no increased risk of brain tumors.
To confirm their results, Dr. Oster and his coinvestigators also conducted a sensitivity analysis limited to the 55,079 children and adolescents with at least two outpatient or one inpatient ICD-9 diagnostic code for congenital heart disease. Here the incidence of childhood malignancies was 5.1/1,000 patients, for an overall 6.4-fold increased relative risk.
“Bedside-to-bench work is now needed to determine potential mechanisms,” he said. “We believe the increased risk is related more to a common genetic pathway than to an exposure or treatment pathway because it occurs so early. But there may be some impact of exposures or treatment as well. We think that radiation exposure is more of a longer-term risk.”
He and his coinvestigators next plan to look at the impact on pediatric cancer risk of specific types of congenital heart defects.
Dr. Oster reported having no financial conflicts of interest regarding this study, which received Centers for Disease Control and Prevention funding.
NEW ORLEANS – Children with congenital heart defects have a five- to sixfold increased risk of developing pediatric cancer, Matthew Oster, MD, reported at the American Heart Association scientific sessions.
“The absolute risk is small, but it’s still a five- to sixfold risk compared to the general pediatric population, and it does warrant monitoring and a high index of suspicion in our children with congenital heart defects,” said Dr. Oster of Children’s Healthcare of Atlanta.
The increased cancer risk in adults with congenital heart defects has recently been the focus of research attention. However, little is known about the risk of cancer during the childhood of patients with congenital heart defects.
This was the impetus for Dr. Oster’s nationwide retrospective study of 6.1 million children and adolescents continuously enrolled in private, employer-sponsored health insurance plans during 2009-2015. The data came from the Truven Health MarketScan administrative database.
Children with Down syndrome were excluded from the study because their condition is known to be associated with increased rates of both congenital heart defects and pediatric cancers.
Among 88,493 individuals under age 18 with a diagnosed congenital heart defect, the incidence of any neoplasm diagnosed at least 30 days after diagnosis of the heart defect was 3.91/1,000, compared with 0.79/1,000 in more than 6 million children and adolescents without congenital heart disease.
Thus, children with a congenital heart defect were at a 4.9-fold increased risk for developing a childhood cancer. The risk for bone tumors was 11.2-fold greater than in the general pediatric population, and their neuroblastoma risk was 9.8-fold greater. Their risks of lymphoma and leukemia were increased 5.2- and 2.8-fold, respectively. Of note, they had no increased risk of brain tumors.
To confirm their results, Dr. Oster and his coinvestigators also conducted a sensitivity analysis limited to the 55,079 children and adolescents with at least two outpatient or one inpatient ICD-9 diagnostic code for congenital heart disease. Here the incidence of childhood malignancies was 5.1/1,000 patients, for an overall 6.4-fold increased relative risk.
“Bedside-to-bench work is now needed to determine potential mechanisms,” he said. “We believe the increased risk is related more to a common genetic pathway than to an exposure or treatment pathway because it occurs so early. But there may be some impact of exposures or treatment as well. We think that radiation exposure is more of a longer-term risk.”
He and his coinvestigators next plan to look at the impact on pediatric cancer risk of specific types of congenital heart defects.
Dr. Oster reported having no financial conflicts of interest regarding this study, which received Centers for Disease Control and Prevention funding.
NEW ORLEANS – Children with congenital heart defects have a five- to sixfold increased risk of developing pediatric cancer, Matthew Oster, MD, reported at the American Heart Association scientific sessions.
“The absolute risk is small, but it’s still a five- to sixfold risk compared to the general pediatric population, and it does warrant monitoring and a high index of suspicion in our children with congenital heart defects,” said Dr. Oster of Children’s Healthcare of Atlanta.
The increased cancer risk in adults with congenital heart defects has recently been the focus of research attention. However, little is known about the risk of cancer during the childhood of patients with congenital heart defects.
This was the impetus for Dr. Oster’s nationwide retrospective study of 6.1 million children and adolescents continuously enrolled in private, employer-sponsored health insurance plans during 2009-2015. The data came from the Truven Health MarketScan administrative database.
Children with Down syndrome were excluded from the study because their condition is known to be associated with increased rates of both congenital heart defects and pediatric cancers.
Among 88,493 individuals under age 18 with a diagnosed congenital heart defect, the incidence of any neoplasm diagnosed at least 30 days after diagnosis of the heart defect was 3.91/1,000, compared with 0.79/1,000 in more than 6 million children and adolescents without congenital heart disease.
Thus, children with a congenital heart defect were at a 4.9-fold increased risk for developing a childhood cancer. The risk for bone tumors was 11.2-fold greater than in the general pediatric population, and their neuroblastoma risk was 9.8-fold greater. Their risks of lymphoma and leukemia were increased 5.2- and 2.8-fold, respectively. Of note, they had no increased risk of brain tumors.
To confirm their results, Dr. Oster and his coinvestigators also conducted a sensitivity analysis limited to the 55,079 children and adolescents with at least two outpatient or one inpatient ICD-9 diagnostic code for congenital heart disease. Here the incidence of childhood malignancies was 5.1/1,000 patients, for an overall 6.4-fold increased relative risk.
“Bedside-to-bench work is now needed to determine potential mechanisms,” he said. “We believe the increased risk is related more to a common genetic pathway than to an exposure or treatment pathway because it occurs so early. But there may be some impact of exposures or treatment as well. We think that radiation exposure is more of a longer-term risk.”
He and his coinvestigators next plan to look at the impact on pediatric cancer risk of specific types of congenital heart defects.
Dr. Oster reported having no financial conflicts of interest regarding this study, which received Centers for Disease Control and Prevention funding.
AT THE AHA SCIENTIFIC SESSIONS
Key clinical point:
Major finding: Children with congenital heart defects are at a roughly sixfold increased risk of developing a pediatric cancer.
Data source: A retrospective analysis of administrative health insurance plan data on 6.1 million U.S. subjects under age 18 years, more than 88,000 of whom had congenital heart defects.
Disclosures: The presenter reported having no financial conflicts of interest regarding this study, which received Centers for Disease Control and Prevention funding.
First-trimester blood glucose predicts congenital heart disease risk
NEW ORLEANS – A single, random, first-trimester maternal plasma glucose measurement is superior to an oral glucose tolerance test later in pregnancy as a predictor of congenital heart disease in newborns, Emmi Helle, MD, reported at the American Heart Association scientific sessions.
This finding from a large retrospective study, if confirmed in a prospective data set, is likely to be practice changing. At present, a 1-hour oral glucose tolerance test in the second or third trimester is considered the best means of identifying pregnant women who ought to undergo fetal echocardiography for prenatal diagnosis of congenital heart disease, noted Dr. Helle of Stanford (Calif.) University.
An elevated random plasma glucose value in the first trimester was broadly predictive of increased risk for a variety of congenital heart anomalies, not just, for example, cyanotic conditions.
Fetal heart development is completed during the first trimester, Dr. Helle observed.
Her study received a warm reception. Michael A. Portman, MD, singled it out in his final-day wrap-up of the meeting’s highlights in the field of congenital heart disease.
Several studies have demonstrated that prenatal diagnosis of congenital heart disease results in improved surgical outcomes in newborns. The question is, how to get the right women – those at increased risk – to diagnostic fetal echocardiography. Guidelines suggest but don’t mandate on the basis of weak evidence that an oral glucose tolerance test performed in the second or early third trimester may be a useful means of screening mothers for fetal imaging. Dr. Helle’s study points to a better way.
“Hopefully we can change our guidelines and make them more scientific for identification of mothers who should undergo fetal echocardiography,” said Dr. Portman, professor of pediatrics at the University of Washington, Seattle, and director of pediatric cardiovascular research at Seattle Children’s Hospital.
Dr. Helle and Dr. Portman reported having no relevant financial interests.
NEW ORLEANS – A single, random, first-trimester maternal plasma glucose measurement is superior to an oral glucose tolerance test later in pregnancy as a predictor of congenital heart disease in newborns, Emmi Helle, MD, reported at the American Heart Association scientific sessions.
This finding from a large retrospective study, if confirmed in a prospective data set, is likely to be practice changing. At present, a 1-hour oral glucose tolerance test in the second or third trimester is considered the best means of identifying pregnant women who ought to undergo fetal echocardiography for prenatal diagnosis of congenital heart disease, noted Dr. Helle of Stanford (Calif.) University.
An elevated random plasma glucose value in the first trimester was broadly predictive of increased risk for a variety of congenital heart anomalies, not just, for example, cyanotic conditions.
Fetal heart development is completed during the first trimester, Dr. Helle observed.
Her study received a warm reception. Michael A. Portman, MD, singled it out in his final-day wrap-up of the meeting’s highlights in the field of congenital heart disease.
Several studies have demonstrated that prenatal diagnosis of congenital heart disease results in improved surgical outcomes in newborns. The question is, how to get the right women – those at increased risk – to diagnostic fetal echocardiography. Guidelines suggest but don’t mandate on the basis of weak evidence that an oral glucose tolerance test performed in the second or early third trimester may be a useful means of screening mothers for fetal imaging. Dr. Helle’s study points to a better way.
“Hopefully we can change our guidelines and make them more scientific for identification of mothers who should undergo fetal echocardiography,” said Dr. Portman, professor of pediatrics at the University of Washington, Seattle, and director of pediatric cardiovascular research at Seattle Children’s Hospital.
Dr. Helle and Dr. Portman reported having no relevant financial interests.
NEW ORLEANS – A single, random, first-trimester maternal plasma glucose measurement is superior to an oral glucose tolerance test later in pregnancy as a predictor of congenital heart disease in newborns, Emmi Helle, MD, reported at the American Heart Association scientific sessions.
This finding from a large retrospective study, if confirmed in a prospective data set, is likely to be practice changing. At present, a 1-hour oral glucose tolerance test in the second or third trimester is considered the best means of identifying pregnant women who ought to undergo fetal echocardiography for prenatal diagnosis of congenital heart disease, noted Dr. Helle of Stanford (Calif.) University.
An elevated random plasma glucose value in the first trimester was broadly predictive of increased risk for a variety of congenital heart anomalies, not just, for example, cyanotic conditions.
Fetal heart development is completed during the first trimester, Dr. Helle observed.
Her study received a warm reception. Michael A. Portman, MD, singled it out in his final-day wrap-up of the meeting’s highlights in the field of congenital heart disease.
Several studies have demonstrated that prenatal diagnosis of congenital heart disease results in improved surgical outcomes in newborns. The question is, how to get the right women – those at increased risk – to diagnostic fetal echocardiography. Guidelines suggest but don’t mandate on the basis of weak evidence that an oral glucose tolerance test performed in the second or early third trimester may be a useful means of screening mothers for fetal imaging. Dr. Helle’s study points to a better way.
“Hopefully we can change our guidelines and make them more scientific for identification of mothers who should undergo fetal echocardiography,” said Dr. Portman, professor of pediatrics at the University of Washington, Seattle, and director of pediatric cardiovascular research at Seattle Children’s Hospital.
Dr. Helle and Dr. Portman reported having no relevant financial interests.
AT THE AHA SCIENTIFIC SESSIONS
Key clinical point:
Major finding: For every 10-mg/dL increase in maternal plasma glucose on a random first-trimester measurement, the risk of giving birth to a baby with congenital heart disease rose by 8%.
Data source: A retrospective study of 19,197 pregnancies, 811 of which resulted in congenital heart disease in the offspring.
Disclosures: The presenter reported having no financial conflicts of interest regarding the study.
FDA warning: General anesthetics may damage young brains
The Food and Drug Administration has issued a warning that repeated or lengthy use of general anesthetic and sedation drugs during surgeries or procedures in children younger than 3 years or in pregnant women during their third trimester may affect the development of children’s brains.
“Recent human studies suggest that a single, relatively short exposure to general anesthetic and sedation drugs in infants or toddlers is unlikely to have negative effects on behavior or learning.” The studies suggesting a problem with longer or repeat exposures “had limitations, and it is unclear whether any negative effects seen in children’s learning or behavior were due to the drugs or to other factors, such as the underlying medical condition that led to the need for the surgery or procedure.” Further research is needed, the agency said.
FDA is adding its warning to the labels of 11 general anesthetics and sedatives, including desflurane, halothane, ketamine, lorazepam injection, methohexital, pentobarbital, and propofol. The drugs block N-methyl-D-aspartate (NMDA) receptors and/or potentiate gamma-aminobutyric acid (GABA) activity. No specific medications have been shown to be safer than any other, the agency said.
FDA will continue to monitor the situation, and update its warning as additional information comes in. “We urge health care professionals, patients, parents, and caregivers to report side effects involving anesthetic and sedation drugs or other medicines to the FDA MedWatch program,” the FDA said.
The Food and Drug Administration has issued a warning that repeated or lengthy use of general anesthetic and sedation drugs during surgeries or procedures in children younger than 3 years or in pregnant women during their third trimester may affect the development of children’s brains.
“Recent human studies suggest that a single, relatively short exposure to general anesthetic and sedation drugs in infants or toddlers is unlikely to have negative effects on behavior or learning.” The studies suggesting a problem with longer or repeat exposures “had limitations, and it is unclear whether any negative effects seen in children’s learning or behavior were due to the drugs or to other factors, such as the underlying medical condition that led to the need for the surgery or procedure.” Further research is needed, the agency said.
FDA is adding its warning to the labels of 11 general anesthetics and sedatives, including desflurane, halothane, ketamine, lorazepam injection, methohexital, pentobarbital, and propofol. The drugs block N-methyl-D-aspartate (NMDA) receptors and/or potentiate gamma-aminobutyric acid (GABA) activity. No specific medications have been shown to be safer than any other, the agency said.
FDA will continue to monitor the situation, and update its warning as additional information comes in. “We urge health care professionals, patients, parents, and caregivers to report side effects involving anesthetic and sedation drugs or other medicines to the FDA MedWatch program,” the FDA said.
The Food and Drug Administration has issued a warning that repeated or lengthy use of general anesthetic and sedation drugs during surgeries or procedures in children younger than 3 years or in pregnant women during their third trimester may affect the development of children’s brains.
“Recent human studies suggest that a single, relatively short exposure to general anesthetic and sedation drugs in infants or toddlers is unlikely to have negative effects on behavior or learning.” The studies suggesting a problem with longer or repeat exposures “had limitations, and it is unclear whether any negative effects seen in children’s learning or behavior were due to the drugs or to other factors, such as the underlying medical condition that led to the need for the surgery or procedure.” Further research is needed, the agency said.
FDA is adding its warning to the labels of 11 general anesthetics and sedatives, including desflurane, halothane, ketamine, lorazepam injection, methohexital, pentobarbital, and propofol. The drugs block N-methyl-D-aspartate (NMDA) receptors and/or potentiate gamma-aminobutyric acid (GABA) activity. No specific medications have been shown to be safer than any other, the agency said.
FDA will continue to monitor the situation, and update its warning as additional information comes in. “We urge health care professionals, patients, parents, and caregivers to report side effects involving anesthetic and sedation drugs or other medicines to the FDA MedWatch program,” the FDA said.
Expandable cardiac valve in children found feasible
Young children and infants who require cardiac valve replacement are limited to fixed-diameter prostheses that cannot accommodate their growth, but researchers at Boston Children’s Hospital have reinforced an expandable bovine jugular vein graft using an external stent and implanted it in 42 patients with acceptable short-term results, according to a report in the Journal of Thoracic and Cardiovascular Surgery.
In 4 years, the modified Melody valve (Medtronic) has proved amenable to enlargement via catheterization as the child grows, Sitaram M. Emani, MD, and coauthors said. “The valve was competent with low gradient acutely postoperatively in all patients,” Dr. Emani and his coauthors said (J Thorac Cardiovasc Surg. 2016 Dec;152[6]:1514-23).
The Melody valve is approved for transcatheter implantation into the RVOT and can be modified for the semilunar or AV positions, Dr. Emani and his coauthors said. The valve has achieved competence within a size range of 10-22 mm.
The researchers implanted the valve in four positions: RVOT (14), mitral (24), aortic (one), or tricuspid (three). The median age at implantation was 10 months, with a range of 3 weeks to 5.8 years. The patients had an average of one previous valve replacement or repair procedure.
Six deaths occurred in the study population; three before discharge. Those three patients had replacement to salvage a moribund circulation in the setting of mechanical circulatory support and severely depressed ventricular function. The other three patients who died were able to demonstrate adequate valve function, and autopsy did not show any signs of valvular thrombosis or deterioration, the researchers said.
Using Kaplan-Meier analysis, Dr. Emani and his coauthors estimated the freedom from death or transplantation was 83% at 12 months and 77% at 24 months.
The average time between catheter-based dilations was around 10 months, they wrote, “but this might be increased by more aggressive dilation.” Early in the study, the researchers were not aggressive with dilations because of concerns about valve injury, but then they found that patients tolerated increases in valve diameter by as much as 4 mm.
“Further investigation is needed to determine whether the device retains expandability over the long term after multiple dilations,” Dr. Emani and his coauthors said.
Further refinements in valve design and implantation techniques may lead to prevention of reoperation and perivalvular complications, they suggested.
The researchers did note a couple limitations of their study: the heterogeneous cohort prohibits any generalization of the outcomes, particularly mortality, and concomitant procedures performed during the valve replacement would affect mortality.
Dr. Emani and his colleagues had no financial relationships to disclose.
In his invited commentary, Carl L. Backer, MD, of Northwestern University, Chicago, noted three advantages of the use of the stent-expandable bovine valve for infants and children: It can be used when no prosthetic is small enough to fit in the annulus, it does not require anticoagulation with warfarin after placement, and it can be dilated as the child grows (J Thorac Cardiovasc Surg. 2016 Dec:152[6];1524-5).
But, Dr. Backer added, “one note of caution that I would raise relates to the late complications noted in previous trials with tissue valves on the left side of the heart in children.” He noted such experience had been reported with the Mitroflow bovine pericardial bioprosthesis (LivaNova) (Circulation. 2014;130[1];51-60) and the Perimount Magna (Edwards Lifesciences) (Ann Thorac Surg. 2016;102[1];308-11). “The follow-up of Emani and colleagues at two years is good; however, there is always the possibility that premature calcification and stenosis of these valves, particularly those placed on the left side of the heart, could lead to the need for early explantation,” Dr. Backer said.
Nonetheless, the findings of Dr. Emani and his colleagues showed that the concept of implanting a stented jugular vein graft valve in infants and young children “is proving to be safe and efficacious,” Dr. Backer said. “In these children for whom there are limited options, this appears to be an important addition to our surgical strategies,” he concluded.
Dr. Backer had no financial relationships to disclose.
In his invited commentary, Carl L. Backer, MD, of Northwestern University, Chicago, noted three advantages of the use of the stent-expandable bovine valve for infants and children: It can be used when no prosthetic is small enough to fit in the annulus, it does not require anticoagulation with warfarin after placement, and it can be dilated as the child grows (J Thorac Cardiovasc Surg. 2016 Dec:152[6];1524-5).
But, Dr. Backer added, “one note of caution that I would raise relates to the late complications noted in previous trials with tissue valves on the left side of the heart in children.” He noted such experience had been reported with the Mitroflow bovine pericardial bioprosthesis (LivaNova) (Circulation. 2014;130[1];51-60) and the Perimount Magna (Edwards Lifesciences) (Ann Thorac Surg. 2016;102[1];308-11). “The follow-up of Emani and colleagues at two years is good; however, there is always the possibility that premature calcification and stenosis of these valves, particularly those placed on the left side of the heart, could lead to the need for early explantation,” Dr. Backer said.
Nonetheless, the findings of Dr. Emani and his colleagues showed that the concept of implanting a stented jugular vein graft valve in infants and young children “is proving to be safe and efficacious,” Dr. Backer said. “In these children for whom there are limited options, this appears to be an important addition to our surgical strategies,” he concluded.
Dr. Backer had no financial relationships to disclose.
In his invited commentary, Carl L. Backer, MD, of Northwestern University, Chicago, noted three advantages of the use of the stent-expandable bovine valve for infants and children: It can be used when no prosthetic is small enough to fit in the annulus, it does not require anticoagulation with warfarin after placement, and it can be dilated as the child grows (J Thorac Cardiovasc Surg. 2016 Dec:152[6];1524-5).
But, Dr. Backer added, “one note of caution that I would raise relates to the late complications noted in previous trials with tissue valves on the left side of the heart in children.” He noted such experience had been reported with the Mitroflow bovine pericardial bioprosthesis (LivaNova) (Circulation. 2014;130[1];51-60) and the Perimount Magna (Edwards Lifesciences) (Ann Thorac Surg. 2016;102[1];308-11). “The follow-up of Emani and colleagues at two years is good; however, there is always the possibility that premature calcification and stenosis of these valves, particularly those placed on the left side of the heart, could lead to the need for early explantation,” Dr. Backer said.
Nonetheless, the findings of Dr. Emani and his colleagues showed that the concept of implanting a stented jugular vein graft valve in infants and young children “is proving to be safe and efficacious,” Dr. Backer said. “In these children for whom there are limited options, this appears to be an important addition to our surgical strategies,” he concluded.
Dr. Backer had no financial relationships to disclose.
Young children and infants who require cardiac valve replacement are limited to fixed-diameter prostheses that cannot accommodate their growth, but researchers at Boston Children’s Hospital have reinforced an expandable bovine jugular vein graft using an external stent and implanted it in 42 patients with acceptable short-term results, according to a report in the Journal of Thoracic and Cardiovascular Surgery.
In 4 years, the modified Melody valve (Medtronic) has proved amenable to enlargement via catheterization as the child grows, Sitaram M. Emani, MD, and coauthors said. “The valve was competent with low gradient acutely postoperatively in all patients,” Dr. Emani and his coauthors said (J Thorac Cardiovasc Surg. 2016 Dec;152[6]:1514-23).
The Melody valve is approved for transcatheter implantation into the RVOT and can be modified for the semilunar or AV positions, Dr. Emani and his coauthors said. The valve has achieved competence within a size range of 10-22 mm.
The researchers implanted the valve in four positions: RVOT (14), mitral (24), aortic (one), or tricuspid (three). The median age at implantation was 10 months, with a range of 3 weeks to 5.8 years. The patients had an average of one previous valve replacement or repair procedure.
Six deaths occurred in the study population; three before discharge. Those three patients had replacement to salvage a moribund circulation in the setting of mechanical circulatory support and severely depressed ventricular function. The other three patients who died were able to demonstrate adequate valve function, and autopsy did not show any signs of valvular thrombosis or deterioration, the researchers said.
Using Kaplan-Meier analysis, Dr. Emani and his coauthors estimated the freedom from death or transplantation was 83% at 12 months and 77% at 24 months.
The average time between catheter-based dilations was around 10 months, they wrote, “but this might be increased by more aggressive dilation.” Early in the study, the researchers were not aggressive with dilations because of concerns about valve injury, but then they found that patients tolerated increases in valve diameter by as much as 4 mm.
“Further investigation is needed to determine whether the device retains expandability over the long term after multiple dilations,” Dr. Emani and his coauthors said.
Further refinements in valve design and implantation techniques may lead to prevention of reoperation and perivalvular complications, they suggested.
The researchers did note a couple limitations of their study: the heterogeneous cohort prohibits any generalization of the outcomes, particularly mortality, and concomitant procedures performed during the valve replacement would affect mortality.
Dr. Emani and his colleagues had no financial relationships to disclose.
Young children and infants who require cardiac valve replacement are limited to fixed-diameter prostheses that cannot accommodate their growth, but researchers at Boston Children’s Hospital have reinforced an expandable bovine jugular vein graft using an external stent and implanted it in 42 patients with acceptable short-term results, according to a report in the Journal of Thoracic and Cardiovascular Surgery.
In 4 years, the modified Melody valve (Medtronic) has proved amenable to enlargement via catheterization as the child grows, Sitaram M. Emani, MD, and coauthors said. “The valve was competent with low gradient acutely postoperatively in all patients,” Dr. Emani and his coauthors said (J Thorac Cardiovasc Surg. 2016 Dec;152[6]:1514-23).
The Melody valve is approved for transcatheter implantation into the RVOT and can be modified for the semilunar or AV positions, Dr. Emani and his coauthors said. The valve has achieved competence within a size range of 10-22 mm.
The researchers implanted the valve in four positions: RVOT (14), mitral (24), aortic (one), or tricuspid (three). The median age at implantation was 10 months, with a range of 3 weeks to 5.8 years. The patients had an average of one previous valve replacement or repair procedure.
Six deaths occurred in the study population; three before discharge. Those three patients had replacement to salvage a moribund circulation in the setting of mechanical circulatory support and severely depressed ventricular function. The other three patients who died were able to demonstrate adequate valve function, and autopsy did not show any signs of valvular thrombosis or deterioration, the researchers said.
Using Kaplan-Meier analysis, Dr. Emani and his coauthors estimated the freedom from death or transplantation was 83% at 12 months and 77% at 24 months.
The average time between catheter-based dilations was around 10 months, they wrote, “but this might be increased by more aggressive dilation.” Early in the study, the researchers were not aggressive with dilations because of concerns about valve injury, but then they found that patients tolerated increases in valve diameter by as much as 4 mm.
“Further investigation is needed to determine whether the device retains expandability over the long term after multiple dilations,” Dr. Emani and his coauthors said.
Further refinements in valve design and implantation techniques may lead to prevention of reoperation and perivalvular complications, they suggested.
The researchers did note a couple limitations of their study: the heterogeneous cohort prohibits any generalization of the outcomes, particularly mortality, and concomitant procedures performed during the valve replacement would affect mortality.
Dr. Emani and his colleagues had no financial relationships to disclose.
FROM THE JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY
Key clinical point: An expandable cardiac valve adapted for infants and children demonstrates acceptable function and can accommodate the child’s growth.
Major finding: At 12 months after implantation of a bovine jugular vein graft reinforced with an external stent modified for surgical valve replacement in pediatric patients, Kaplan-Meier analysis indicated that 83% of those surviving would be free from reoperation at 12 months.
Data source: Single-center study of 42 patients who underwent implantation between 2010 and 2014.
Disclosures: Dr. Emani and his coauthors had no financial relationships to disclose.
Lower-risk approach for aortic arch repair
In newborns with a borderline hypoplastic aortic arch, the type of operation and surgical approach can be critical in determining the risk of recurrent obstruction, but aortic arch reconstruction through a median sternotomy on bypass may carry a lower risk of recurrence than use of a thoracotomy.
In a study of 183 newborns and infants (median age of 15 days) who had surgery for coarctation and hypoplastic aortic arch over a 17-year period, researchers led by Andreas Tulzer, MD, of Children’s Heart Center, Linz, Austria, found that resection and extended end-to-end anastomosis (REEEA) as well as end-to-side anastomosis (ESA) yielded low mortality. The findings were published in the December 2016 issue of the Journal of Thoracic and Cardiovascular Surgery (2016;152:1506-13).
In the study, 72 patients had a median sternotomy – 71 with cardiopulmonary bypass (CPB) – and the remaining 111 had a lateral thoracotomy. Fifty-two patients (28.4%) had an additional ventricular septal defect closure. In the 71 patients who had median sternotomy with CPB, 41 had REEEA and 30 had ESA.
One patient who had median sternotomy with CPB had complications whereas 10 who had undergone primary repair with REEEA through a lateral thoracotomy had complications, for complications rates of 1.4% and 9%, respectively.
“Access through a median sternotomy with the use of CPB was superior to a lateral thoracotomy in terms of necessary reinterventions,” noted Dr. Tulzer and coauthors.
Of the 131 patients who had isolated repair of coarctation of the aorta with associated hypoplastic aortic arch, 116 had REEEA and 15 had ESA. There were no in-hospital deaths in this group and one patient needed an early reintervention. One patient had a severe neurologic complication.
On long-term follow-up of 139 patients at a median duration of 6.3 years, no late deaths were reported. “The calculated freedom from mortality (early and late) at 10 years for the entire group was 99.27%,” the researchers said. “In none of the patients of the follow-up population did we notice any signs of permanent left laryngeal nerve injury, bronchial compression, or left pulmonary artery stenosis.”
Lateral thoracotomy as access was a significant risk factor for recurrent obstruction at P = .03.
In the study, an experienced pediatric cardiologist and a pediatric cardiac surgeon determined which of three procedures to use – ESA on bypass, REEEA with a median sternotomy on CPB, or REEEA with a lateral thoracotomy without CPB – based on the size and anatomy of the proximal transverse aortic arch. In the early study period, cut-off values were proximal transverse arch diameters of 4 mm or less in newborns and young infants, but in the later study period the cut-off was z scores of –4.5 or less.
Adverse outcomes were minimal. There was one death within 30 days of surgery in the overall population (0.54%). The one severe complication consisted of paraplegia and cerebral hypoxemia after REEEA. At 10 years, 99.27% of all patients survived and 90.12% were free from intervention.
Either approach with REEEA and ESA is safe and effective, Dr. Tulzer and colleagues said, but they did determine a suitable population for the median sternotomy using CPB. “In patients with proximal transverse aortic arch, z scores of less than –4.59, arch repair should be performed through a median sternotomy using CPB, rather than through a lateral thoracotomy to reduce the risk for recurrent arch obstructions,” the researchers concluded.
Dr. Tulzer and coauthors had no financial relationships to disclose.
While the outcomes that Dr. Tulzer and colleagues reported are “remarkable,” the findings raise a question if mortality and risk of interventions are the sole determinants in selecting a surgical strategy, Petros V. Anagnostopoulos, MD, said in his invited commentary (J Thorac Cardiovasc Surg. 2016;152:1475-6). “The mortality should be low irrespective of approach,” Dr. Anagnostopoulos said.
He said that even if the surgeon pursues repair for coarctation and hypoplastic aortic arch through a thoracotomy instead of the median sternotomy the Austrian authors advocate and coarctation should recur, most of these cases can be treated with catheterization at low risk. “Will such a suboptimal outcome prove to be superior to that of a patient who has perfect anatomic repair but potentially faces adverse neurodevelopmental consequences of a neonatal cardiopulmonary bypass run?” he asked.
But the long-term outcomes are “poorly defined” as clinical investigators continue to “push the limits” to avoid deep hypothermia by using perfusion modifications to perform arch reconstruction, said Dr. Anagnostopoulos of the division of pediatric cardiothoracic surgery, American Family Children’s Hospital, University of Wisconsin, Madison. “It may be time to start taking into account not only survival and accuracy of repair, but also long-term sequelae of our therapies,” he concluded.
Dr. Anagnostopoulos had no financial relationships to disclose.
While the outcomes that Dr. Tulzer and colleagues reported are “remarkable,” the findings raise a question if mortality and risk of interventions are the sole determinants in selecting a surgical strategy, Petros V. Anagnostopoulos, MD, said in his invited commentary (J Thorac Cardiovasc Surg. 2016;152:1475-6). “The mortality should be low irrespective of approach,” Dr. Anagnostopoulos said.
He said that even if the surgeon pursues repair for coarctation and hypoplastic aortic arch through a thoracotomy instead of the median sternotomy the Austrian authors advocate and coarctation should recur, most of these cases can be treated with catheterization at low risk. “Will such a suboptimal outcome prove to be superior to that of a patient who has perfect anatomic repair but potentially faces adverse neurodevelopmental consequences of a neonatal cardiopulmonary bypass run?” he asked.
But the long-term outcomes are “poorly defined” as clinical investigators continue to “push the limits” to avoid deep hypothermia by using perfusion modifications to perform arch reconstruction, said Dr. Anagnostopoulos of the division of pediatric cardiothoracic surgery, American Family Children’s Hospital, University of Wisconsin, Madison. “It may be time to start taking into account not only survival and accuracy of repair, but also long-term sequelae of our therapies,” he concluded.
Dr. Anagnostopoulos had no financial relationships to disclose.
While the outcomes that Dr. Tulzer and colleagues reported are “remarkable,” the findings raise a question if mortality and risk of interventions are the sole determinants in selecting a surgical strategy, Petros V. Anagnostopoulos, MD, said in his invited commentary (J Thorac Cardiovasc Surg. 2016;152:1475-6). “The mortality should be low irrespective of approach,” Dr. Anagnostopoulos said.
He said that even if the surgeon pursues repair for coarctation and hypoplastic aortic arch through a thoracotomy instead of the median sternotomy the Austrian authors advocate and coarctation should recur, most of these cases can be treated with catheterization at low risk. “Will such a suboptimal outcome prove to be superior to that of a patient who has perfect anatomic repair but potentially faces adverse neurodevelopmental consequences of a neonatal cardiopulmonary bypass run?” he asked.
But the long-term outcomes are “poorly defined” as clinical investigators continue to “push the limits” to avoid deep hypothermia by using perfusion modifications to perform arch reconstruction, said Dr. Anagnostopoulos of the division of pediatric cardiothoracic surgery, American Family Children’s Hospital, University of Wisconsin, Madison. “It may be time to start taking into account not only survival and accuracy of repair, but also long-term sequelae of our therapies,” he concluded.
Dr. Anagnostopoulos had no financial relationships to disclose.
In newborns with a borderline hypoplastic aortic arch, the type of operation and surgical approach can be critical in determining the risk of recurrent obstruction, but aortic arch reconstruction through a median sternotomy on bypass may carry a lower risk of recurrence than use of a thoracotomy.
In a study of 183 newborns and infants (median age of 15 days) who had surgery for coarctation and hypoplastic aortic arch over a 17-year period, researchers led by Andreas Tulzer, MD, of Children’s Heart Center, Linz, Austria, found that resection and extended end-to-end anastomosis (REEEA) as well as end-to-side anastomosis (ESA) yielded low mortality. The findings were published in the December 2016 issue of the Journal of Thoracic and Cardiovascular Surgery (2016;152:1506-13).
In the study, 72 patients had a median sternotomy – 71 with cardiopulmonary bypass (CPB) – and the remaining 111 had a lateral thoracotomy. Fifty-two patients (28.4%) had an additional ventricular septal defect closure. In the 71 patients who had median sternotomy with CPB, 41 had REEEA and 30 had ESA.
One patient who had median sternotomy with CPB had complications whereas 10 who had undergone primary repair with REEEA through a lateral thoracotomy had complications, for complications rates of 1.4% and 9%, respectively.
“Access through a median sternotomy with the use of CPB was superior to a lateral thoracotomy in terms of necessary reinterventions,” noted Dr. Tulzer and coauthors.
Of the 131 patients who had isolated repair of coarctation of the aorta with associated hypoplastic aortic arch, 116 had REEEA and 15 had ESA. There were no in-hospital deaths in this group and one patient needed an early reintervention. One patient had a severe neurologic complication.
On long-term follow-up of 139 patients at a median duration of 6.3 years, no late deaths were reported. “The calculated freedom from mortality (early and late) at 10 years for the entire group was 99.27%,” the researchers said. “In none of the patients of the follow-up population did we notice any signs of permanent left laryngeal nerve injury, bronchial compression, or left pulmonary artery stenosis.”
Lateral thoracotomy as access was a significant risk factor for recurrent obstruction at P = .03.
In the study, an experienced pediatric cardiologist and a pediatric cardiac surgeon determined which of three procedures to use – ESA on bypass, REEEA with a median sternotomy on CPB, or REEEA with a lateral thoracotomy without CPB – based on the size and anatomy of the proximal transverse aortic arch. In the early study period, cut-off values were proximal transverse arch diameters of 4 mm or less in newborns and young infants, but in the later study period the cut-off was z scores of –4.5 or less.
Adverse outcomes were minimal. There was one death within 30 days of surgery in the overall population (0.54%). The one severe complication consisted of paraplegia and cerebral hypoxemia after REEEA. At 10 years, 99.27% of all patients survived and 90.12% were free from intervention.
Either approach with REEEA and ESA is safe and effective, Dr. Tulzer and colleagues said, but they did determine a suitable population for the median sternotomy using CPB. “In patients with proximal transverse aortic arch, z scores of less than –4.59, arch repair should be performed through a median sternotomy using CPB, rather than through a lateral thoracotomy to reduce the risk for recurrent arch obstructions,” the researchers concluded.
Dr. Tulzer and coauthors had no financial relationships to disclose.
In newborns with a borderline hypoplastic aortic arch, the type of operation and surgical approach can be critical in determining the risk of recurrent obstruction, but aortic arch reconstruction through a median sternotomy on bypass may carry a lower risk of recurrence than use of a thoracotomy.
In a study of 183 newborns and infants (median age of 15 days) who had surgery for coarctation and hypoplastic aortic arch over a 17-year period, researchers led by Andreas Tulzer, MD, of Children’s Heart Center, Linz, Austria, found that resection and extended end-to-end anastomosis (REEEA) as well as end-to-side anastomosis (ESA) yielded low mortality. The findings were published in the December 2016 issue of the Journal of Thoracic and Cardiovascular Surgery (2016;152:1506-13).
In the study, 72 patients had a median sternotomy – 71 with cardiopulmonary bypass (CPB) – and the remaining 111 had a lateral thoracotomy. Fifty-two patients (28.4%) had an additional ventricular septal defect closure. In the 71 patients who had median sternotomy with CPB, 41 had REEEA and 30 had ESA.
One patient who had median sternotomy with CPB had complications whereas 10 who had undergone primary repair with REEEA through a lateral thoracotomy had complications, for complications rates of 1.4% and 9%, respectively.
“Access through a median sternotomy with the use of CPB was superior to a lateral thoracotomy in terms of necessary reinterventions,” noted Dr. Tulzer and coauthors.
Of the 131 patients who had isolated repair of coarctation of the aorta with associated hypoplastic aortic arch, 116 had REEEA and 15 had ESA. There were no in-hospital deaths in this group and one patient needed an early reintervention. One patient had a severe neurologic complication.
On long-term follow-up of 139 patients at a median duration of 6.3 years, no late deaths were reported. “The calculated freedom from mortality (early and late) at 10 years for the entire group was 99.27%,” the researchers said. “In none of the patients of the follow-up population did we notice any signs of permanent left laryngeal nerve injury, bronchial compression, or left pulmonary artery stenosis.”
Lateral thoracotomy as access was a significant risk factor for recurrent obstruction at P = .03.
In the study, an experienced pediatric cardiologist and a pediatric cardiac surgeon determined which of three procedures to use – ESA on bypass, REEEA with a median sternotomy on CPB, or REEEA with a lateral thoracotomy without CPB – based on the size and anatomy of the proximal transverse aortic arch. In the early study period, cut-off values were proximal transverse arch diameters of 4 mm or less in newborns and young infants, but in the later study period the cut-off was z scores of –4.5 or less.
Adverse outcomes were minimal. There was one death within 30 days of surgery in the overall population (0.54%). The one severe complication consisted of paraplegia and cerebral hypoxemia after REEEA. At 10 years, 99.27% of all patients survived and 90.12% were free from intervention.
Either approach with REEEA and ESA is safe and effective, Dr. Tulzer and colleagues said, but they did determine a suitable population for the median sternotomy using CPB. “In patients with proximal transverse aortic arch, z scores of less than –4.59, arch repair should be performed through a median sternotomy using CPB, rather than through a lateral thoracotomy to reduce the risk for recurrent arch obstructions,” the researchers concluded.
Dr. Tulzer and coauthors had no financial relationships to disclose.
FROM THE JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY
Key clinical point: Aortic arch reconstruction through a median sternotomy on bypass in newborns and infants had lower rates for recurrent obstruction than did a thoracotomy approach.
Major finding: Of 11 patients who required reintervention, one had a median sternotomy and 10 had a lateral thoracotomy.
Data source: Retrospective review of 183 consecutive newborns and infants with coarctation and hypoplastic aortic arch from 1996 to 2013.
Disclosures: Dr. Tulzer and coauthors had no financial relationships to disclose.
Evaluating Fontan failure risk after arrhythmia
People who have undergone the Fontan procedure have been known to be prone to developing arrhythmias, but few studies have evaluated their prognosis, so researchers from Australia and New Zealand analyzed results of more than 1,000 patients with Fontan circulation and found that two-thirds did not have any arrhythmia at 20 years, and that, among those who did have arrhythmias, almost three-quarters survived 10 years.
“After the first onset of an arrhythmia, close surveillance of ventricular function is required,” Thomas A. Carins, MD, and his colleagues reported (J Thorac Cardiovasc Surg. 2016;152:1355-63). They analyzed data from 1,034 patients who had Fontan procedures from 1975 to 2014 in the Australia and New Zealand Fontan Registry. “The development of an arrhythmia is associated with a heightened risk of subsequent failure of the Fontan circulation,” they wrote.
The study aimed to determine the type of arrhythmias Fontan patients had and what impact that had on long-term outcomes. The most common Fontan approach used in study patients was the extracardiac conduit (555), followed by the lateral tunnel approach (269) and atriopulmonary (210). Those who had the extracardiac Fontan were least likely to develop an arrhythmia, with a hazard ratio of 0.23 (P less than .001), which Dr. Carins and his coauthors noted was in line with previous reports of arrhythmias occurring in patients who had undergone the atriopulmonary connection (Circulation. 2004;109:2319-25; J Thorac Cardiovasc Surg. 1998;115:499-505).
Overall, 195 patients in the study developed arrhythmia, with 162 having tachyarrhythmia, 74 having bradyarrhythmia and 41 having both. “At 20 years, freedom from any arrhythmia, tachyarrhythmia, and bradyarrhythmia was 66%, 69%, and 85%, respectively,” the researchers said.
The following outcomes occurred after the first onset of arrhythmia – tachyarrhythmia in 153 patients and bradyarrhythmia in 42: Thirty-three died; 12 had heart transplants, 30 had a Fontan correction to an extracardiac conduit, three had a Fontan takedown, 12 developed enteropathy, and 25 developed New York Heart Association class III or IV symptoms. Eighty-four patients reached the composite endpoint of Fontan failure.
After they developed arrhythmias, most patients in all three Fontan procedure groups remained free from Fontan failure at 10 years: 67% in the extracardiac conduit group; 54% in the lateral tunnel group; and 51% in the atriopulmonary group.
Medical management of up to four medications was the preferred initial treatment for those with tachyarrhythmias (86%); 101 patients had a single episode of tachyarrhythmia at follow-up intervals of four to 13 years (7.6 year median). “Those who experienced a single versus multiple episodes of tachyarrhythmia showed comparable freedom from Fontan failure at 15 years,” noted Dr. Carins and his coauthors – with rates of 34% and 33%, respectively. Of the 74 patients with bradyarrhythmias, 66 received pacemakers.
“Survival after the onset of an arrhythmia was surprisingly good with 67% and 84% of patients alive at 10 years after the onset of a tachyarrhythmia and bradyarrhythmia, respectively,” the study authors said. “There was no association between occurrence of arrhythmia and survival.”
About 40% of the patients with a tachyarrhythmia or bradyarrhythmia in the study had reduced ventricular function at 10 years after onset, the researchers wrote. “Although the assessment of ventricular function in this study was clearly subjective, we nonetheless believe that these findings suggest that the onset of an arrhythmia is associated with a progressive deterioration in cardiac function,”they noted.
Coauthor Andrew Bullock, MBBS, disclosed receiving consulting fees from Actelion. Dr. Cairns and other coauthors had no financial relationships to disclose.
When interpreting the data that the Australian and New Zealand researchers analyzed, one must be cautious about viewing arrhythmia as an early indicator for Fontan revision, Mark E. Alexander, MD, of Boston Children’s Hospital and Harvard Medical School, said in his invited commentary (J Thorac Cardiovasc Surg. 2016;152:1364-5).
The outcome of a Fontan revision after an arrhythmia “becomes self-fulfilling,” Dr. Alexander said. He questioned what the revision procedure would be when the initial operation was an extracardiac Fontan. “The complex risks of that procedure continue to keep decisions regarding Fontan revisions challenging,” he said. He also noted the study did not analyze the association of ventricular function and arrhythmias “in a substantive way.”
And Dr. Alexander did not interpret the study results as an endorsement of the extracardiac Fontan or a rejection of the lateral tunnel approach. The early adoption of the extracardiac Fontan by the groups the authors represented is itself a limitation of the study, he said. Challenges with follow-up of extracardiac techniques in this and other studies “limit our ability to declare a ‘victor’ in that debate,” he said. “It does remind the electrophysiologist that he or she needs to master the techniques of entering the pulmonary venous atrium in these patients.”
The precision of calculating risk after an operation grows weaker with time, he said, and at 15-20 years morbidity starts to increase and follow-up becomes “more diffuse,” Dr. Alexander said. “That reality means we look forward to this group continuing to enhance our understanding of how our changing management decisions can aid our patients.”
Dr. Alexander had no financial relationships to disclose.
When interpreting the data that the Australian and New Zealand researchers analyzed, one must be cautious about viewing arrhythmia as an early indicator for Fontan revision, Mark E. Alexander, MD, of Boston Children’s Hospital and Harvard Medical School, said in his invited commentary (J Thorac Cardiovasc Surg. 2016;152:1364-5).
The outcome of a Fontan revision after an arrhythmia “becomes self-fulfilling,” Dr. Alexander said. He questioned what the revision procedure would be when the initial operation was an extracardiac Fontan. “The complex risks of that procedure continue to keep decisions regarding Fontan revisions challenging,” he said. He also noted the study did not analyze the association of ventricular function and arrhythmias “in a substantive way.”
And Dr. Alexander did not interpret the study results as an endorsement of the extracardiac Fontan or a rejection of the lateral tunnel approach. The early adoption of the extracardiac Fontan by the groups the authors represented is itself a limitation of the study, he said. Challenges with follow-up of extracardiac techniques in this and other studies “limit our ability to declare a ‘victor’ in that debate,” he said. “It does remind the electrophysiologist that he or she needs to master the techniques of entering the pulmonary venous atrium in these patients.”
The precision of calculating risk after an operation grows weaker with time, he said, and at 15-20 years morbidity starts to increase and follow-up becomes “more diffuse,” Dr. Alexander said. “That reality means we look forward to this group continuing to enhance our understanding of how our changing management decisions can aid our patients.”
Dr. Alexander had no financial relationships to disclose.
When interpreting the data that the Australian and New Zealand researchers analyzed, one must be cautious about viewing arrhythmia as an early indicator for Fontan revision, Mark E. Alexander, MD, of Boston Children’s Hospital and Harvard Medical School, said in his invited commentary (J Thorac Cardiovasc Surg. 2016;152:1364-5).
The outcome of a Fontan revision after an arrhythmia “becomes self-fulfilling,” Dr. Alexander said. He questioned what the revision procedure would be when the initial operation was an extracardiac Fontan. “The complex risks of that procedure continue to keep decisions regarding Fontan revisions challenging,” he said. He also noted the study did not analyze the association of ventricular function and arrhythmias “in a substantive way.”
And Dr. Alexander did not interpret the study results as an endorsement of the extracardiac Fontan or a rejection of the lateral tunnel approach. The early adoption of the extracardiac Fontan by the groups the authors represented is itself a limitation of the study, he said. Challenges with follow-up of extracardiac techniques in this and other studies “limit our ability to declare a ‘victor’ in that debate,” he said. “It does remind the electrophysiologist that he or she needs to master the techniques of entering the pulmonary venous atrium in these patients.”
The precision of calculating risk after an operation grows weaker with time, he said, and at 15-20 years morbidity starts to increase and follow-up becomes “more diffuse,” Dr. Alexander said. “That reality means we look forward to this group continuing to enhance our understanding of how our changing management decisions can aid our patients.”
Dr. Alexander had no financial relationships to disclose.
People who have undergone the Fontan procedure have been known to be prone to developing arrhythmias, but few studies have evaluated their prognosis, so researchers from Australia and New Zealand analyzed results of more than 1,000 patients with Fontan circulation and found that two-thirds did not have any arrhythmia at 20 years, and that, among those who did have arrhythmias, almost three-quarters survived 10 years.
“After the first onset of an arrhythmia, close surveillance of ventricular function is required,” Thomas A. Carins, MD, and his colleagues reported (J Thorac Cardiovasc Surg. 2016;152:1355-63). They analyzed data from 1,034 patients who had Fontan procedures from 1975 to 2014 in the Australia and New Zealand Fontan Registry. “The development of an arrhythmia is associated with a heightened risk of subsequent failure of the Fontan circulation,” they wrote.
The study aimed to determine the type of arrhythmias Fontan patients had and what impact that had on long-term outcomes. The most common Fontan approach used in study patients was the extracardiac conduit (555), followed by the lateral tunnel approach (269) and atriopulmonary (210). Those who had the extracardiac Fontan were least likely to develop an arrhythmia, with a hazard ratio of 0.23 (P less than .001), which Dr. Carins and his coauthors noted was in line with previous reports of arrhythmias occurring in patients who had undergone the atriopulmonary connection (Circulation. 2004;109:2319-25; J Thorac Cardiovasc Surg. 1998;115:499-505).
Overall, 195 patients in the study developed arrhythmia, with 162 having tachyarrhythmia, 74 having bradyarrhythmia and 41 having both. “At 20 years, freedom from any arrhythmia, tachyarrhythmia, and bradyarrhythmia was 66%, 69%, and 85%, respectively,” the researchers said.
The following outcomes occurred after the first onset of arrhythmia – tachyarrhythmia in 153 patients and bradyarrhythmia in 42: Thirty-three died; 12 had heart transplants, 30 had a Fontan correction to an extracardiac conduit, three had a Fontan takedown, 12 developed enteropathy, and 25 developed New York Heart Association class III or IV symptoms. Eighty-four patients reached the composite endpoint of Fontan failure.
After they developed arrhythmias, most patients in all three Fontan procedure groups remained free from Fontan failure at 10 years: 67% in the extracardiac conduit group; 54% in the lateral tunnel group; and 51% in the atriopulmonary group.
Medical management of up to four medications was the preferred initial treatment for those with tachyarrhythmias (86%); 101 patients had a single episode of tachyarrhythmia at follow-up intervals of four to 13 years (7.6 year median). “Those who experienced a single versus multiple episodes of tachyarrhythmia showed comparable freedom from Fontan failure at 15 years,” noted Dr. Carins and his coauthors – with rates of 34% and 33%, respectively. Of the 74 patients with bradyarrhythmias, 66 received pacemakers.
“Survival after the onset of an arrhythmia was surprisingly good with 67% and 84% of patients alive at 10 years after the onset of a tachyarrhythmia and bradyarrhythmia, respectively,” the study authors said. “There was no association between occurrence of arrhythmia and survival.”
About 40% of the patients with a tachyarrhythmia or bradyarrhythmia in the study had reduced ventricular function at 10 years after onset, the researchers wrote. “Although the assessment of ventricular function in this study was clearly subjective, we nonetheless believe that these findings suggest that the onset of an arrhythmia is associated with a progressive deterioration in cardiac function,”they noted.
Coauthor Andrew Bullock, MBBS, disclosed receiving consulting fees from Actelion. Dr. Cairns and other coauthors had no financial relationships to disclose.
People who have undergone the Fontan procedure have been known to be prone to developing arrhythmias, but few studies have evaluated their prognosis, so researchers from Australia and New Zealand analyzed results of more than 1,000 patients with Fontan circulation and found that two-thirds did not have any arrhythmia at 20 years, and that, among those who did have arrhythmias, almost three-quarters survived 10 years.
“After the first onset of an arrhythmia, close surveillance of ventricular function is required,” Thomas A. Carins, MD, and his colleagues reported (J Thorac Cardiovasc Surg. 2016;152:1355-63). They analyzed data from 1,034 patients who had Fontan procedures from 1975 to 2014 in the Australia and New Zealand Fontan Registry. “The development of an arrhythmia is associated with a heightened risk of subsequent failure of the Fontan circulation,” they wrote.
The study aimed to determine the type of arrhythmias Fontan patients had and what impact that had on long-term outcomes. The most common Fontan approach used in study patients was the extracardiac conduit (555), followed by the lateral tunnel approach (269) and atriopulmonary (210). Those who had the extracardiac Fontan were least likely to develop an arrhythmia, with a hazard ratio of 0.23 (P less than .001), which Dr. Carins and his coauthors noted was in line with previous reports of arrhythmias occurring in patients who had undergone the atriopulmonary connection (Circulation. 2004;109:2319-25; J Thorac Cardiovasc Surg. 1998;115:499-505).
Overall, 195 patients in the study developed arrhythmia, with 162 having tachyarrhythmia, 74 having bradyarrhythmia and 41 having both. “At 20 years, freedom from any arrhythmia, tachyarrhythmia, and bradyarrhythmia was 66%, 69%, and 85%, respectively,” the researchers said.
The following outcomes occurred after the first onset of arrhythmia – tachyarrhythmia in 153 patients and bradyarrhythmia in 42: Thirty-three died; 12 had heart transplants, 30 had a Fontan correction to an extracardiac conduit, three had a Fontan takedown, 12 developed enteropathy, and 25 developed New York Heart Association class III or IV symptoms. Eighty-four patients reached the composite endpoint of Fontan failure.
After they developed arrhythmias, most patients in all three Fontan procedure groups remained free from Fontan failure at 10 years: 67% in the extracardiac conduit group; 54% in the lateral tunnel group; and 51% in the atriopulmonary group.
Medical management of up to four medications was the preferred initial treatment for those with tachyarrhythmias (86%); 101 patients had a single episode of tachyarrhythmia at follow-up intervals of four to 13 years (7.6 year median). “Those who experienced a single versus multiple episodes of tachyarrhythmia showed comparable freedom from Fontan failure at 15 years,” noted Dr. Carins and his coauthors – with rates of 34% and 33%, respectively. Of the 74 patients with bradyarrhythmias, 66 received pacemakers.
“Survival after the onset of an arrhythmia was surprisingly good with 67% and 84% of patients alive at 10 years after the onset of a tachyarrhythmia and bradyarrhythmia, respectively,” the study authors said. “There was no association between occurrence of arrhythmia and survival.”
About 40% of the patients with a tachyarrhythmia or bradyarrhythmia in the study had reduced ventricular function at 10 years after onset, the researchers wrote. “Although the assessment of ventricular function in this study was clearly subjective, we nonetheless believe that these findings suggest that the onset of an arrhythmia is associated with a progressive deterioration in cardiac function,”they noted.
Coauthor Andrew Bullock, MBBS, disclosed receiving consulting fees from Actelion. Dr. Cairns and other coauthors had no financial relationships to disclose.
FROM THE JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY
Key clinical point: The development of arrhythmia is associated with a heightened risk of failure of Fontan circulation after a Fontan procedure.
Major finding: At 20 years, freedom from any arrhythmia was 66%, and after the onset of any arrhythmia freedom from Fontan failure was 55%.
Data source: 1,034 patients who had undergone a Fontan procedure from 1975 to 2014 as recorded in the Australian and New Zealand Fontan Registry.
Disclosures: Coauthor Andrew Bullock, MBBS, reported receiving consulting fees from Actelion. All other others have no financial relationships to disclose.
Newborns with CHD have reduced cerebral oxygen delivery
Using a newer form of MRI to investigate oxygen levels in newborns with congenital heart disease, researchers in Canada reported that these patients may have impaired brain growth and development in the first weeks of life because of significantly lower cerebral oxygen delivery levels.
These findings suggest that oxygen delivery may impact brain growth, particularly in newborns with single-ventricle physiology, reported Jessie Mei Lim, BSc, of the University of Toronto, and her colleagues from McGill University, Montreal, and the Hospital for Sick Children, Toronto. The findings were published in the October issue of the Journal of Thoracic and Cardiovascular Surgery (2016;152:1095-103). Ms. Lim and her colleagues used cine phase-contrast (PC) MRI to measure cerebral blood flow in newborns with congenital heard disease (CHD). Previous studies used optical measures of tissue oxygenation and MRI arterial spin labeling to suggests that newborns with severe CHD have impaired CBF and cerebral oxygen delivery (CDO2) and CBF.
This single-center study involved 63 newborns from June 2013 to April 2015 at the Hospital for Sick Children. These subjects received an MRI of the head before surgery at an average of age 7.5 days. The scans were done without sedation or contrast while the infants were asleep. The study compared 31 age-matched controls with 32 subjects with various forms of CHD – 12 were managed surgically along a single-ventricle pathway (SVP), 4 had coarctation of the aorta, 13 had transposition of the great arteries (TGA), and 3 had other forms of CHD.
The researchers validated their method by reporting similarities between flows in the basilar and vertebral arteries in 14 controls, “suggesting good consistency and accuracy of our method for measuring CBF,” Ms. Lim and her coauthors noted. A comparison of CBF measured with an unpaired Student t test revealed no significant differences between the CHD group and controls. The average net CBF in CHD patients was 103.5 mL/min vs. 119.7 mL/min in controls.
However, when evaluating CDO2 using a Student t test, the researchers found significantly lower levels in the CHD group – an average of 1,1881 mLO2/min. vs. 2,712 mL O2/min in controls (P less than .0001). And when the researchers indexed CDO2 to brain volume yielding indexed oxygen delivery, the difference between the two groups was still significant: an average of 523.1 mL O2/min-1 .100 g-1 in the CHD group and 685.6 mL O2/min-1.100 g-1 in controls (P = .0006).
Among the CHD group, those with SVP and TGA had significantly lower CDO2 than that of controls. Brain volumes were also lower in those with CHD (mean of 338.5 mL vs. 377.7 mL in controls, P = .002).
The MRI findings were telling in the study population, Ms. Lim and her coauthors said. Five subjects in the CHD group had a combination of diffuse excessive high-signal intensity (DEHSI) and white-matter injury (WMI), 10 had an isolated finding of DEHSI, two had WMI alone and five others had other minor brain abnormalities. But the control group had no abnormal findings on conventional brain MRI.
The researchers acknowledged that, while the impact of reduced cerebral oxygen delivery is unknown, “theoretical reasons for thinking it might adversely impact ongoing brain growth and development during this period of rapid brain growth are considered.”
Cardiovascular surgeons should consider these findings when deciding on when to operate on newborns with CHD, the researchers said. “Further support for the concept that such a mechanism could lead to irreversible deficits in brain growth and development might result in attempts to expedite surgical repair of congenital cardiac lesions, which have conventionally not been addressed in the neonatal period,” they wrote.
Ms. Lim and her coauthors had no financial relationships to disclose.
Congenital heart disease (CHD) is heterogeneous and different types of lesions may cause different hemodynamics, Caitlin K. Rollins, MD, of Boston Children’s Hospital and Harvard Medical School said in her invited commentary (J Thorac Cardiovasc Surg. 2016;152-960-1).
Ms. Lim and her colleagues in this study confirmed that premise with their finding that newborns with CHD and controls had similar cerebral blood flow, but that those with CHD had reduced oxygen delivery. “These differences were most apparent in the neonates with single-ventricle physiology and transposition of the great arteries,” Dr. Rollins said. The study authors’ finding of an association between reduced oxygen delivery and impaired brain development, along with this group’s previous reports (Circulation 2015;131:1313-23) suggesting preserved cerebral blood flow in the late prenatal period, differ from other studies using traditional methods to show reduced cerebral blood flow in obstructive left-sided lesions, Dr. Rollins said. “Although technical differences may in part account for the discrepancy, the contrasting results also reflect that the relative contributions of abnormal cerebral blood flow and oxygenation differ among forms of CHD,” Dr. Rollins said.
Congenital heart disease (CHD) is heterogeneous and different types of lesions may cause different hemodynamics, Caitlin K. Rollins, MD, of Boston Children’s Hospital and Harvard Medical School said in her invited commentary (J Thorac Cardiovasc Surg. 2016;152-960-1).
Ms. Lim and her colleagues in this study confirmed that premise with their finding that newborns with CHD and controls had similar cerebral blood flow, but that those with CHD had reduced oxygen delivery. “These differences were most apparent in the neonates with single-ventricle physiology and transposition of the great arteries,” Dr. Rollins said. The study authors’ finding of an association between reduced oxygen delivery and impaired brain development, along with this group’s previous reports (Circulation 2015;131:1313-23) suggesting preserved cerebral blood flow in the late prenatal period, differ from other studies using traditional methods to show reduced cerebral blood flow in obstructive left-sided lesions, Dr. Rollins said. “Although technical differences may in part account for the discrepancy, the contrasting results also reflect that the relative contributions of abnormal cerebral blood flow and oxygenation differ among forms of CHD,” Dr. Rollins said.
Congenital heart disease (CHD) is heterogeneous and different types of lesions may cause different hemodynamics, Caitlin K. Rollins, MD, of Boston Children’s Hospital and Harvard Medical School said in her invited commentary (J Thorac Cardiovasc Surg. 2016;152-960-1).
Ms. Lim and her colleagues in this study confirmed that premise with their finding that newborns with CHD and controls had similar cerebral blood flow, but that those with CHD had reduced oxygen delivery. “These differences were most apparent in the neonates with single-ventricle physiology and transposition of the great arteries,” Dr. Rollins said. The study authors’ finding of an association between reduced oxygen delivery and impaired brain development, along with this group’s previous reports (Circulation 2015;131:1313-23) suggesting preserved cerebral blood flow in the late prenatal period, differ from other studies using traditional methods to show reduced cerebral blood flow in obstructive left-sided lesions, Dr. Rollins said. “Although technical differences may in part account for the discrepancy, the contrasting results also reflect that the relative contributions of abnormal cerebral blood flow and oxygenation differ among forms of CHD,” Dr. Rollins said.
Using a newer form of MRI to investigate oxygen levels in newborns with congenital heart disease, researchers in Canada reported that these patients may have impaired brain growth and development in the first weeks of life because of significantly lower cerebral oxygen delivery levels.
These findings suggest that oxygen delivery may impact brain growth, particularly in newborns with single-ventricle physiology, reported Jessie Mei Lim, BSc, of the University of Toronto, and her colleagues from McGill University, Montreal, and the Hospital for Sick Children, Toronto. The findings were published in the October issue of the Journal of Thoracic and Cardiovascular Surgery (2016;152:1095-103). Ms. Lim and her colleagues used cine phase-contrast (PC) MRI to measure cerebral blood flow in newborns with congenital heard disease (CHD). Previous studies used optical measures of tissue oxygenation and MRI arterial spin labeling to suggests that newborns with severe CHD have impaired CBF and cerebral oxygen delivery (CDO2) and CBF.
This single-center study involved 63 newborns from June 2013 to April 2015 at the Hospital for Sick Children. These subjects received an MRI of the head before surgery at an average of age 7.5 days. The scans were done without sedation or contrast while the infants were asleep. The study compared 31 age-matched controls with 32 subjects with various forms of CHD – 12 were managed surgically along a single-ventricle pathway (SVP), 4 had coarctation of the aorta, 13 had transposition of the great arteries (TGA), and 3 had other forms of CHD.
The researchers validated their method by reporting similarities between flows in the basilar and vertebral arteries in 14 controls, “suggesting good consistency and accuracy of our method for measuring CBF,” Ms. Lim and her coauthors noted. A comparison of CBF measured with an unpaired Student t test revealed no significant differences between the CHD group and controls. The average net CBF in CHD patients was 103.5 mL/min vs. 119.7 mL/min in controls.
However, when evaluating CDO2 using a Student t test, the researchers found significantly lower levels in the CHD group – an average of 1,1881 mLO2/min. vs. 2,712 mL O2/min in controls (P less than .0001). And when the researchers indexed CDO2 to brain volume yielding indexed oxygen delivery, the difference between the two groups was still significant: an average of 523.1 mL O2/min-1 .100 g-1 in the CHD group and 685.6 mL O2/min-1.100 g-1 in controls (P = .0006).
Among the CHD group, those with SVP and TGA had significantly lower CDO2 than that of controls. Brain volumes were also lower in those with CHD (mean of 338.5 mL vs. 377.7 mL in controls, P = .002).
The MRI findings were telling in the study population, Ms. Lim and her coauthors said. Five subjects in the CHD group had a combination of diffuse excessive high-signal intensity (DEHSI) and white-matter injury (WMI), 10 had an isolated finding of DEHSI, two had WMI alone and five others had other minor brain abnormalities. But the control group had no abnormal findings on conventional brain MRI.
The researchers acknowledged that, while the impact of reduced cerebral oxygen delivery is unknown, “theoretical reasons for thinking it might adversely impact ongoing brain growth and development during this period of rapid brain growth are considered.”
Cardiovascular surgeons should consider these findings when deciding on when to operate on newborns with CHD, the researchers said. “Further support for the concept that such a mechanism could lead to irreversible deficits in brain growth and development might result in attempts to expedite surgical repair of congenital cardiac lesions, which have conventionally not been addressed in the neonatal period,” they wrote.
Ms. Lim and her coauthors had no financial relationships to disclose.
Using a newer form of MRI to investigate oxygen levels in newborns with congenital heart disease, researchers in Canada reported that these patients may have impaired brain growth and development in the first weeks of life because of significantly lower cerebral oxygen delivery levels.
These findings suggest that oxygen delivery may impact brain growth, particularly in newborns with single-ventricle physiology, reported Jessie Mei Lim, BSc, of the University of Toronto, and her colleagues from McGill University, Montreal, and the Hospital for Sick Children, Toronto. The findings were published in the October issue of the Journal of Thoracic and Cardiovascular Surgery (2016;152:1095-103). Ms. Lim and her colleagues used cine phase-contrast (PC) MRI to measure cerebral blood flow in newborns with congenital heard disease (CHD). Previous studies used optical measures of tissue oxygenation and MRI arterial spin labeling to suggests that newborns with severe CHD have impaired CBF and cerebral oxygen delivery (CDO2) and CBF.
This single-center study involved 63 newborns from June 2013 to April 2015 at the Hospital for Sick Children. These subjects received an MRI of the head before surgery at an average of age 7.5 days. The scans were done without sedation or contrast while the infants were asleep. The study compared 31 age-matched controls with 32 subjects with various forms of CHD – 12 were managed surgically along a single-ventricle pathway (SVP), 4 had coarctation of the aorta, 13 had transposition of the great arteries (TGA), and 3 had other forms of CHD.
The researchers validated their method by reporting similarities between flows in the basilar and vertebral arteries in 14 controls, “suggesting good consistency and accuracy of our method for measuring CBF,” Ms. Lim and her coauthors noted. A comparison of CBF measured with an unpaired Student t test revealed no significant differences between the CHD group and controls. The average net CBF in CHD patients was 103.5 mL/min vs. 119.7 mL/min in controls.
However, when evaluating CDO2 using a Student t test, the researchers found significantly lower levels in the CHD group – an average of 1,1881 mLO2/min. vs. 2,712 mL O2/min in controls (P less than .0001). And when the researchers indexed CDO2 to brain volume yielding indexed oxygen delivery, the difference between the two groups was still significant: an average of 523.1 mL O2/min-1 .100 g-1 in the CHD group and 685.6 mL O2/min-1.100 g-1 in controls (P = .0006).
Among the CHD group, those with SVP and TGA had significantly lower CDO2 than that of controls. Brain volumes were also lower in those with CHD (mean of 338.5 mL vs. 377.7 mL in controls, P = .002).
The MRI findings were telling in the study population, Ms. Lim and her coauthors said. Five subjects in the CHD group had a combination of diffuse excessive high-signal intensity (DEHSI) and white-matter injury (WMI), 10 had an isolated finding of DEHSI, two had WMI alone and five others had other minor brain abnormalities. But the control group had no abnormal findings on conventional brain MRI.
The researchers acknowledged that, while the impact of reduced cerebral oxygen delivery is unknown, “theoretical reasons for thinking it might adversely impact ongoing brain growth and development during this period of rapid brain growth are considered.”
Cardiovascular surgeons should consider these findings when deciding on when to operate on newborns with CHD, the researchers said. “Further support for the concept that such a mechanism could lead to irreversible deficits in brain growth and development might result in attempts to expedite surgical repair of congenital cardiac lesions, which have conventionally not been addressed in the neonatal period,” they wrote.
Ms. Lim and her coauthors had no financial relationships to disclose.
FROM THE JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY
Key clinical point: Cerebral blood flow is maintained but cerebral oxygen delivery is decreased in preoperative newborns with cyanotic congenital heart disease (CHD).
Major finding: Average cerebral oxygen delivery measured 1,1881 mLO2/min in the CHD group when measured with Student t testing vs. 2,712 mLO2/min in controls (P less than .0001).
Data source: Single-center study of 32 neonates with various forms of CHD 31 age-matched controls.
Disclosures: Ms. Lim and coauthors have no financial relationships to disclose.