A comparative clinical study was made of patients undergone prosthetic bifurcation grafting for non-ruptured abdominal aortic aneurysm n = 135 or aortoiliac occlusive disease n = 180 between January 1982 and December 1986. Patients in aneurysmal group were older, predominantly men, had hypertension more often and had better distal run-off at the time of operation. Smoking was over-presented among aortoiliac occlusive disease patients. Patients operated for abdominal aortic aneurysms had better early and late graft patency rates and lower late amputation rates. There were no significant differences in operative mortality rates and late survival rates between occlusive disease and aneurysmal patients. Cardiac mortality mainly reduced early and late survival rates in both patient groups. We should begin to use systematically a reliable and non-invasive method for screening the myocardial status in patients who are going to be operated for abdominal aortic aneurysm or aortoiliac occlusive disease.