Abstract
A 76-year-old woman presented with anterolateral ST-segment elevation myocardial infarction complicated by incessant ventricular arrhythmia. Angiography did not find obstructive coronary disease. Echocardiography demonstrated "double valve sign," pathognomonic of aortic dissection, which was subsequently confirmed on computed tomography. The coronary arteries arose from the true lumen; thus, it was understood that her presentation was caused by external coronary ostia compression by the growing false aortic lumen. It has long been understood that when aortic dissection involves the coronary arteries, it typically affects the right artery. This case highlights a rare complication of aortic dissection affecting the left coronary artery.