One of the newest trends in pulmonary embolism management is treatment of cancer associated venous thromboembolism (VTE) which encompasses deep vein thrombosis (DVT) and PE. Following the clinical management of cancer-associated venous thromboembolism in the hospital, direct oral anticoagulant therapy at discharge is your starting point, except in cases of intact luminal cancers, Scott Kaatz, DO, MSc, FACP, SFHM, said during SHM Converge, the annual conference of the Society of Hospital Medicine.
Dr. Kaatz, of the division of hospital medicine at Henry Ford Hospital, Detroit, based his remarks on emerging recommendations from leading medical societies on the topic, as well as a one-page algorithm from the Anticoagulation Forum that can be accessed at https://acforum-excellence.org/Resource-Center/resource_files/1638-2020-11-30-121425.pdf.
For the short-term treatment of VTE (3-6 months) for patients with active cancer, the American Society of Hematology guideline panel suggests direct oral anticoagulants, such as apixaban, edoxaban, or rivaroxaban, over low-molecular-weight heparin (LMWH) – a conditional recommendation based on low certainty in the evidence of effects.
Dr. Kaatz also discussed the latest recommendations regarding length of VTE treatment. After completion of primary treatment for patients with DVT and/or PE provoked by a chronic risk factor such as a surgery, pregnancy, or having a leg in a cast, the ASH guideline panel suggests indefinite antithrombotic therapy over stopping anticoagulation. “On the other hand, patients with DVT and/or PE provoked by a transient factor typically do not require antithrombotic therapy after completion of primary treatment,” said Dr. Kaatz, who is also a clinical professor of medicine at Wayne State University, Detroit.
After completion of primary treatment for patients with unprovoked DVT and/or PE, the ASH guideline panel suggests indefinite antithrombotic therapy over stopping anticoagulation. “The recommendation does not apply to patients who have a high risk for bleeding complications,” he noted.
Transient or reversible risk factors should be also considered in length of VTE treatment. For example, according to guidelines from the European Society of Cardiology, the estimated risk for long-term VTE recurrence is high (defined as greater than 8% per year) for patients with active cancer, for patients with one or more previous episodes of VTE in the absence of a major transient or reversible factor, and for those with antiphospholipid antibody syndrome.
Dr. Kaatz also highlighted recommendations for the acute treatment of intermediate risk, or submassive PE. The ESC guidelines state that if anticoagulation is initiated parenterally, LMWH or fondaparinux is recommended over unfractionated heparin (UFH) for most patients. “The reason for that is, one drug-use evaluation study found that, after 24 hours using UFH, only about 24% of patients had reached their therapeutic goal,” Dr. Kaatz said. Guidelines for intermediate risk patients from ASH recommend anticoagulation as your starting point, while thrombolysis is reasonable to consider for submassive PE and low risk for bleeding in selected younger patients or for patients at high risk for decompensation because of concomitant cardiopulmonary disease. “The bleeding rates get much higher in patients over age 65,” he said.
Another resource Dr. Kaatz mentioned is the Pulmonary Embolism Response Team (PERT) Consortium, which was developed after initial efforts of a multidisciplinary team of physicians at Massachusetts General Hospital. The first PERT sought to coordinate and expedite the treatment of pulmonary embolus with a team of physicians from a variety of specialties. In 2019 the PERT Consortium published guidelines on the diagnosis, treatment, and follow-up of acute PE. “It includes detailed algorithms that are a little different from the ASH and ESC guidelines,” Dr. Kaatz said.
Dr. Kaatz disclosed that he is a consultant for Janssen, Pfizer, Portola/Alexion, Bristol-Myers Squibb, Novartis, and CSL Behring. He has also received research funding from Janssen, Bristol-Myers Squibb, and Osmosis. He also holds board positions with the AC Forum and the National Blood Clot Alliance Medical and Scientific Advisory Board.