Embolization of atheroma from the ascending aorta is a major cause of stroke following cardiac surgery. We evaluated a protocol for intraoperative detection and treatment of the severely atherosclerotic ascending aorta which included epiaortic ultrasonographic scanning and resection and graft replacement of the involved segment using hypothermic ischemic arrest. During an 81-month interval, 47 patients 50 years of age and older (mean age 71 years) who underwent coronary artery bypass grafting had resection and graft replacement of the ascending aorta. This represented approximately 2% of the patients in this age group who had cardiac operations during this interval. Nineteen patients (40%) required additional procedures. The 30-day mortality rate was 4.3% (2 patients). Both patients died of myocardial failure. None of the 45 surviving patients sustained a perioperative stroke. There have been no strokes or transient ischemic events in the follow-up period, which extends to 72 months (mean 21 months). While this technique for management of the severely atherosclerotic aorta could be considered radical, it was associated with lower mortality and stroke rates than those that were observed in patients with moderate or severe atherosclerosis in whom only minor modifications in technique were made to avoid embolization of atheroma. Resection and graft replacement during a period of hypothermic circulatory arrest is currently our preferred method of treatment for the severely atherosclerotic aorta during cardiac surgery.