Heparin Resistance — Clinical Perspectives and Management Strategies

This review article outlines the mechanisms, diagnosis, and management strategies for heparin resistance, defined as failure to achieve anticoagulation despite adequate dosing of unfractionated heparin. It explores pharmacologic differences between unfractionated and low-molecular-weight heparin, highlighting the importance of antithrombin-dependent inhibition of thrombin and factor Xa. Causes of resistance include nonspecific protein binding, antithrombin deficiency, elevated coagulation factor levels, platelet interactions, and acute-phase inflammatory responses (e.g. in COVID-19). Laboratory approaches such as anti-factor Xa and aPTT testing are compared, and alternative therapies including antithrombin supplementation and direct thrombin inhibitors (argatroban, bivalirudin) are discussed. The article emphasizes precise diagnostic testing and tailored anticoagulation approaches in critically ill or high-risk patients.

This review article outlines the mechanisms, diagnosis, and management strategies for heparin resistance, defined as failure to achieve anticoagulation despite adequate dosing of unfractionated heparin. It explores pharmacologic differences between unfractionated and low-molecular-weight heparin, highlighting the importance of antithrombin-dependent inhibition of thrombin and factor Xa. Causes of resistance include nonspecific protein binding, antithrombin deficiency, elevated coagulation factor levels, platelet interactions, and acute-phase inflammatory responses (e.g. in COVID-19). Laboratory approaches such as anti-factor Xa and aPTT testing are compared, and alternative therapies including antithrombin supplementation and direct thrombin inhibitors (argatroban, bivalirudin) are discussed. The article emphasizes precise diagnostic testing and tailored anticoagulation approaches in critically ill or high-risk patients.