Anticoagulation Strategies for Cardiopulmonary Bypass in Heparin-Induced Thrombocytopenia: A Brief Review and Practical Algorithm.

Heparin-induced thrombocytopenia (HIT) represents a high-risk perioperative challenge in patients undergoing cardiac surgery. Although unfractionated heparin remains the standard anticoagulant for cardiopulmonary bypass (CPB), its use in patients with current or prior HIT requires careful risk stratification and individualized planning. While several anticoagulation strategies have been described in the literature, available information remains fragmented and lacks concise, practical guidance integrating HIT phase, surgical urgency, renal function, and emerging heparin-enabling therapies. This review provides a clinically focused synthesis of HIT in the cardiac surgical population, encompassing epidemiology, pathophysiology, disease phases, and diagnostic approaches, including considerations specific to patients undergoing CPB. The article discusses the use of bivalirudin and its limitations, particularly in patients with renal dysfunction. It also examines evolving heparin-enabling strategies, including therapeutic plasma exchange, intravenous immunoglobulin, protamine infusion, and antiplatelet agents, designed to reduce antibody burden, mitigate platelet activation, and allow for carefully controlled heparin exposure in selected high-risk patients. Based on current evidence and guideline recommendations, an algorithmic decision-making framework is proposed that incorporates antibody status, functional assay results, surgical urgency, and patient-specific factors. This structured approach aims to support multidisciplinary teams in selecting the safest and most appropriate anticoagulation strategy for patients with acute, subacute, or remote HIT undergoing cardiac surgery.