Acute Profound Thrombocytopenia after Using Abciximab for No-Reflow during Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction
A 65 year-old man with hypertension visited the local hospital with resting chest pain for 3 hours. He was transferred to our hospital due to the abnormal electrocardiogram (ECG) findings showing an elevated ST-segment in the inferior wall territory with a reciprocal change, which was suspicious of STEMI. In the emergency room, blood pressure was 140/80 mm Hg and chest radiography showed no definite abnormal findings, which was graded as Killip class 1. It was decided to have the patient undergo primary PCI for the treatment of STEMI. Conventional medical treatments that include a bolus injection of 5000 IU of heparin, a loading dose of aspirin (300 mg), and clopidogrel (300 mg) was applied before primary PCI. Coronary angiography (CAG) showed a totally occluded lesion of the proximal right coronary artery (RCA) with collateral flow grade 1 from the left anterior descending artery (). After predilatation with a 2.0×20 mm conventional balloon, a bare metal stent 5.0×24 mm Liberte® (Boston Scientific, Natick, MA, USA) was implanted in the proximal RCA lesion (). After implantation of a stent, no-reflow phenomenon developed () and blood pressure decreased with findings of a complete atrioventricular-block and re-elevation of the ST-segment on ECG monitoring. The patient was treated with intracoronary injection of nitrate and adenosine, and intravenous bolus consecutive injection of abciximab with maintenance (intravenous bolus of 0.25 mg/kg, 10 to 60 minutes during the procedure, followed by 0.125 µg/kg/min infusion for 12 hours). Although an improvement was observed in the Thrombolysis in Myocardial Infarction flow grade from grade 0 to grade 3 () and the patient returned to sinus rhythm, the hypotension was sustained. Therefore, an IABP was inserted into the left femoral artery. The patient was moved to the coronary care unit for intensive monitoring with maintenance of abciximab and IABP.\nAlthough the baseline platelet count was 167000/µL before PCI, a routine check determined a complete blood count showing a decreased platelet count of 6000/µL at 22 hours after bolus administration of abciximab, followed by a platelet count of 3000/µL 4 hours later. It was considered that the patient had acute, profound thrombocytopenia as a complication of abciximab. Heparin induced thrombocytopenia (HIT) was excluded because HIT typically develops after 6 to 10 days of heparin use with no previous exposure to heparin. In this case, the patient had no history of exposure to heparin. Therefore, the patient was started on clopidogrel 75 mg/day and aspirin 100 mg/day were started to prevent stent thrombosis. The patient was administered 4 units of platelet concentrates as a precaution. The patient was withdrawn from heparin treatment in consideration of additional hemorrhagic risk, but not HIT. The next followed count of platelet increased to 24000/µL without clinical evidence of stent thrombosis, such as chest pain and a change of ST-segment on ECG. Vital signs were stabilized the next day and IABP was removed successfully using the closing device, Perclose® (Abbott, Redwood City, CA, USA) due to the hemorrhagic risk of the access site and a decreased platelet count of 26000/µL. After additional transfusions of 4 units of platelet concentrates, the platelet count increased to 49000/µL without complications. Subsequently, the platelet count rose to 164000/µL on discharge (). A 1-year follow up of CAG showed good flow of RCA without chest pain or thrombocytopenia.