Approximately 20% of coronary artery anomalies produce sudden death or life-threatening symptoms, including arrhythmias, syncope, and myocardial infarction. The most common clinical symptom of coronary artery anomaly is angina or exertional syncope. Physical examination is usually unrevealing in the absence of myocardial infarction or symptoms of ongoing ischemia. The rapid advent of cardiac computed tomography (CT) technology has made it an important adjunct to the diagnosis of coronary anomalies by angiography. The authors describe the case of a 54-year-old white man who presented with gangrenous toes. He had severe peripheral vascular disease, a femoral-popliteal bypass graft, residual hemiparesis from an ischemic stroke, hypertension, deep vein thrombosis, and a recent myocardial infarction. He underwent a 64-slice cardiac CT angiogram, which showed an interarterial course of the left main coronary artery between the aorta and the pulmonary trunk.