Heparin induced thrombocytopenia with thrombosis: a two step process?

Abstract

Heparin induced thrombocytopaenia is an increasingly recognised prothrombotic disorder, where platelet activation by immunoglobulin G, heparin and platelet factor 4 complexes has been proposed to result in the activation of coagulation, and thrombus formation. However, this pathophysiological mechanism will not explain the predilection of patients, undergoing surgical procedures, especially orthopaedic surgeries, for the development of thrombosis secondary to heparin induced thrombocytopaenia. The article describes a two-step process, where a quantitative role for platelet factor 4 in activating monocytes at the tissue injury sites may play a role in the pathogenesis of heparin induced thrombocytopenia with thrombosis.