Suspected clopidogrel resistance in a patient with acute stent thrombosis

Background A 67-year-old man with supraventricular tachycardia associated with angina underwent coronary angiographic assessment. This investigation revealed mild coronary artery disease in his left main coronary artery and significant stenosis of the ramus medianus (left intermediate artery). A drug-eluting stent was deployed and treatment with clopidogrel and eptifibatide started. The patient subsequently developed chest pain accompanied by hypotension, hypoxemia and electrocardiographic changes that indicated acute myocardial infarction. Emergency angiography revealed occlusion of the ramus medianus despite clopidogrel therapy. Investigations Coronary angiography, hypercoagulable work up and platelet function tests. Diagnosis Acute stent thrombosis and suspected clopidogrel resistance, culminating in ST-segment elevation myocardial infarction after percutaneous coronary intervention. Management Warfarin, aspirin and clopidogrel drug therapy.