Coronary arteriosclerosis seriously complicates the surgical treatment of aortic diseases. The aim of our retrospective study was to determine the incidence of coronary artery disease among our surgical patients in treatment for aortic dissection or aneurysm, and to determine whether coronary intervention before aortic surgery appears to affect outcomes. Between January 1993 and 1 March 1998, our center treated 253 patients for aortic dissection or aneurysm. We examined these cases retrospectively for information on diagnostic and treatment methods, both for the aortic lesions and for concomitant coronary arteriosclerosis. Aortic dissection had been detected in 86 (33.9%) patients and aortic aneurysm in 167 (66.1%). Coronary angiography was performed to search for concomitant coronary artery disease in 29 (33.8%) patients with dissection and in 112 (67.1%) patients with aneurysm; of these, 11 (12.7%) and 54 (32.3%), respectively, were found to have coronary disease. Among 43 patients with abdominal aortic aneurysm in whom coronary angiography was performed concomitant coronary disease was detected in 36 (83.7%). Coronary artery bypass surgery was performed in 10 patients who had dissection and in 30 patients who had aneurysm; percutaneous transluminal coronary angioplasty was performed in 7 patients who had aneurysm. Perioperative mortality rates in the dissection and aneurysm groups, overall, were 23.2% and 13.8%, respectively.