Alternative Anticoagulation for Patients with Heparin-Induced Thrombocytopenia on ECMO: A Narrative Review

Extracorporeal membrane oxygenation (ECMO) is a continuously evolving and increasingly utilized life-support therapy. ECMO requires systemic anticoagulation, which exposes patients to an increased risk of heparin-induced thrombocytopenia (HIT). Clinical experience with alternative anticoagulants in this setting remains limited. The 2022 Extracorporeal Life Support Organization (ELSO)-Anticoagulation Guidelines provide no specific recommendations regarding anticoagulant selection for ECMO patients with HIT. This article aims to review current practices, available evidence, and most recent advances concerning the use of alternative anticoagulants in ECMO patients with HIT. In patients with a high suspicion or confirmed diagnosis of HIT, management includes discontinuing all forms of heparin exposure and initiating an alternative anticoagulant, such as a direct thrombin inhibitor and/or factor Xa inhibitor. Direct thrombin inhibitors act independently of antithrombin and have a short half-life, providing a more consistent and predictable anticoagulation effect. Most available data, primarily from retrospective studies, describe the use of argatroban in ECMO patients with HIT. Bivalirudin has also been used as an alternative anticoagulant in this population, with no significant increase in bleeding or thrombotic complications. However, the current evidence remains limited to small, retrospective, single-center or case-control studies. Fondaparinux has shown effectiveness in the HIT setting and appears to have a low risk of complications. Factor XIIa inhibitors represent a novel class of anticoagulants currently under investigation, evaluated only in animal models. Growing clinical experience with alternative anticoagulants, particularly direct thrombin inhibitors, suggests that their use will likely become a primary focus in ECMO anticoagulation management in the coming years.