The clinical outcome of 99 patients who underwent combined single-stage carotid thromboendarterectomy and coronary artery bypass grafts in three different hospitals over a 15-year period was analyzed. Coronary revascularization was elective in 16 patients, urgent in 46 and emergent in 37 patients. Asymptomatic carotid artery stenosis of greater than or equal to 80% was detected in 79% of patients. Sequential reconstruction of the carotid artery circulation followed by restoration of the coronary circulation was performed in all patients by two separate surgical teams. The population included 79 men and 20 women, with a mean age of 67 +/- 6 years, of whom 53% had a previous myocardial infarction, 59% had hypertension and 49% had a history of smoking. Three or more coronary arteries were revascularized in 90% of patients. The overall major neurological complication rate was 25%, with an 11% stroke rate ipsilateral to the operated carotid. Other major complications included respiratory failure (5%), multisystem failure (8%), and myocardial infarction (8%). The overall mortality was 12%. Ten of the 12 deaths were directly related to the cardiac operation, and 2 died as a result of stroke. We conclude that a combined carotid and coronary artery operation results in a high morbidity and mortality in institutions with excellent records for each operation when performed separately. Whenever possible, these high risk patients should be carefully assessed regarding the need for both procedures, since prophylactic carotid endarterectomy has not been shown to significantly reduce the neurologic risk of coronary bypass.