Death due to undetected heparin-induced thrombocytopenia after cardiac surgery.

A 41-year-old male patient was diagnosed acute myocardial infarction. An intra-aortic balloon pump was inserted to treat heart failure, and off-pump coronary artery bypass surgery was performed. Postoperative cardiac catheterization revealed occlusion of all the 3 bypass grafts, and percutaneous coronary intervention (PCI) was performed. Thrombosis due to heparin-induced thrombocytopenia (HIT) occurred during PCI, which was completed after switching to argatroban based on the possible HIT. Cardiopulmonary arrest occurred suddenly after PCI, and the patient died. Undetected HIT may have caused the sudden change. HIT should be suspected and aggressively treated when thrombocytopenia occurs even during assisted circulation.