Arteriosclerotic aneurysms of the coronary arteries.

The majority of aneurysms of the coronary arteries are due to arteriosclerosis. Fusiform aneurysms are common. Because the natural history of these aneurysms and their role in the pathogenesis of myocardial infarction are not clear, neither excision nor repair is justified. Bypass surgery is indicated if proximal obstruction is present. Saccular aneurysms, on the other hand, are prone to rupture and thrombosis and therefore require repair. Three illustrative cases are presented with one successful repair.