ISTH guidelines for antithrombotic treatment in COVID‐19

Abstract

Antithrombotic agents reduce risk of thromboembolism in severely ill patients. Patients with coronavirus disease 2019 (COVID‐19) may realize additional benefits from heparins. Optimal dosing and timing of these treatments and benefits of other antithrombotic agents remain unclear. In October 2021, ISTH assembled an international panel of content experts, patient representatives, and a methodologist to develop recommendations on anticoagulants and antiplatelet agents for patients with COVID‐19 in different clinical settings. We used the American College of Cardiology Foundation/American Heart Association methodology to assess level of evidence (LOE) and class of recommendation (COR). Only recommendations with LOE A or B were included. Panelists agreed on 12 recommendations: three for non‐hospitalized, five for non–critically ill hospitalized, three for critically ill hospitalized, and one for post‐discharge patients. Two recommendations were based on high‐quality evidence, the remainder on moderate‐quality evidence. Among non–critically ill patients hospitalized for COVID‐19, the panel gave a strong recommendation (a) for use of prophylactic dose of low molecular weight heparin or unfractionated heparin (LMWH/UFH) (COR 1); (b) for select patients in this group, use of therapeutic dose LMWH/UFH in preference to prophylactic dose (COR 1); but (c) against the addition of an antiplatelet agent (COR 3). Weak recommendations favored (a) sulodexide in non‐hospitalized patients, (b) adding an antiplatelet agent to prophylactic LMWH/UFH in select critically ill, and (c) prophylactic rivaroxaban for select patients after discharge (all COR 2b). Recommendations in this guideline are based on high‐/moderate‐quality evidence available through March 2022. Focused updates will incorporate future evidence supporting changes to these recommendations.

Evaluation of a fast‐and‐frugal clinical decision algorithm (‘pathways’) on clinical outcomes in hospitalised patients with COVID‐19 treated with anticoagulants

“…Does delivery of prophylactic anticoagulation via FFT‐algorithm provide support for the ASH 25 and ISTH 35 guidelines recommending antithrombotic treatment with LMWH at prophylactic rather than therapeutic‐intensity doses in hospitalised patients with COVID‐19 at low risk to progression to critical diseases? In populations with the very low VTE, death and bleeding rates we observed, this is likely the case particularly when this regimen may improve important hospital outcomes such as the length of stay and averting admission to the ICU.…”

“… 24 , 25 The latter is also echoed by International Society on Thrombosis and Haemostasis (ISTH), which issued a strong recommendation for the use of prophylactic over therapeutic anticoagulation for non–critically ill hospitalised patients with COVID‐19. 35 …”

COVID-19-Associated Pulmonary Embolism: Review of the Pathophysiology, Epidemiology, Prevention, Diagnosis, and Treatment

“…Professional and scientific organizations have integrated the current evidence and published clinical guidelines for the management of antithrombotic therapy in patients with COVID-19. 93 94 95 96 These recommendations extend beyond PE, per se, and include the risk of venous or arterial thrombosis, organ support, mortality, and bleeding. The recommendations are divided according to the severity of the disease and outpatient or inpatient settings.…”

Disseminated Intravascular Coagulation: The Past, Present, and Future Considerations

“…Currently, the effects of anticoagulants are actively being examined, and the results will be feedback to other types of coagulopathies. 48…”