Fifty-three of 203 consecutive carotid endarterectomies (26%) performed on the Neurosurgical Service at the University of Iowa were in patients over 70 years of age (mean age, 73.4). This series included 38 men and 15 women. Thirty-three patients (62%) presented with transient ischemic attacks, and the remaining 38% were functional stroke patients. Medical risk factors in this group included hypertension in 70%, previous myocardial infarction in 26%, angina in 17%, peripheral vascular disease in 23%, and diabetes in 13%. Sixty-four per cent of the patients had been previously treated with antihypertensive drugs, 43% with antiplatelet agents, and 4% with anticoagulants. Noninvasive vascular evaluation was performed in 25 of 53 (47%) patients, and all underwent angiography before operation. There were no angiographic complications. All patients were operated on with full-channel electroencephalographic (EEG) monitoring. Indwelling shunts were required in 6 of 53 (11%) cases. Intraoperative heparin was given and not reversed; the mean dose was 5100 units. The mean clamp time was 48 minutes. Patch grafts, fashioned from common facial or saphenous veins, were used in 2 patients. Eight patients had contralateral carotid occlusions, but only 2 (25%) required indwelling shunt placement based on EEG criteria. There were no perioperative deaths in this series. One patient had a postoperative stroke, and 1 patient had a postoperative nonfatal myocardial infarction. Transient surgical complications included 3 wound hematomas, 1 wound abscess, and 2 self-limited cranial nerve palsies (13%).(ABSTRACT TRUNCATED AT 250 WORDS)