A Case of Heparin-Induced Thrombocytopenia (HIT) Diagnosed Which Waiting for Off-Pump Coronary Artery Bypass Grafting

A 67-year-old man had angina pectoris due to left main trunk stenosis of coronary artery was transferred to our hospital. Anticoagulation was achieved with a continuous intravenous infusion of 625IU/h heparin. Sixteen days after admission, his platelet count decreased to 14×104/μl, and further decreased to 9.1×104/μl 4 days later. Since we suspected HIT, heparin administration was immediately discontinued, and was substituted with argatroban. A definitive diagnosis of type II HIT was made by a serologic test confirming positive antibodies to the heparin-platelet factor 4 (PF4) complexes. After the platelet count recovered, we performed off-pump CABG (OPCAB) using argatroban. The postoperative course was uneventful and platelet counts was normal. The patient was discharged on the 13th postoperative day. Heparin-induced thrombocytopenia, which causes thrombosis, is a serious side effect of heparin therapy. It is not rare, and in such case argatroban can be useful as an anticoagulant during OPCAB.