Heparin-induced thrombocytopenia and thrombosis syndrome or H.I.T.T.S.

Heparin induced thrombocytopenia has been reported to occur in 10-30% of patients receiving heparin therapy. Approximately 0.6-10% of these patients will develop a rare and poorly recognized paradoxical thrombosis. The suspected mechanism is an IgG mediated immune complex that causes platelet aggregation. Clinical hallmarks include thrombocytopenia, increasing heparin tolerance and recurrent arterial embolism. Laboratory testing as well as treatment modalities are presented. This paper reports on two open-heart surgery cases that developed heparin induced thrombocytopenia and the thrombosis syndrome (H.I.T.T.S.)