Fig. 2From: Apixaban for treatment of confirmed heparin-induced thrombocytopenia: a case report and review of literatureMechanism of heparin-induced thrombocytopenia. Negatively charged heparin binds to positively charged platelet factor-4 (PF-4) forming antigenic multimeric complexes, resulting in IgG formation against these complexes. These antibodies bind to the Fc site on platelets and cause further PF-4 release from alpha-granules. Concurrently, monocytes are activated and release tissue factor, further activating thrombin and propagating endothelial damageBack to article page