Asymptomatic occlusion of the left main coronary artery by an aortic pseudoaneurysm.

Extrinsic compression of the left main coronary artery is a rare cause of coronary ischemia. We describe a 35-year-old Asian woman with complete asymptomatic occlusion of the left main coronary artery by a large aortic pseudoaneurysm. She underwent repair of the pseudoaneurysm and coronary artery bypass grafting at the Mayo Clinic in Rochester, Minn. The differential diagnosis is discussed. Based on this patient's age and associated vascular lesions, we conclude that Takayasu arteritis was the most likely cause of her condition.