A 21 year old man, with no conventional risk factors for coronary artery disease, presented with an acute inferior wall myocardial infarction. The patient was thrombolysed with streptokinase. Transthoracic echocardiography showed good left ventricular function with mild inferior wall hypokinesia. He had no history of Kawasaki’s disease. Selective coronary angiogram of the left coronary artery showed diffuse dilatation of the left main and proximal left anterior descending artery, and the proximal circumflex artery (panels A and B). Selective coronary angiogram of the right coronary artery revealed a dilated proximal coronary artery with thrombus (panel C). The patient was treated with aspirin, clopidogrel and warfarin, and the international normalised ratio (INR) maintained at 2.5. A repeat angiogram 40 days later revealed a recanalised right coronary artery (panel D). The patient was discharged on the same drugs and is doing well at six months follow up.