One hundred and four patients who underwent combined gas endarterectomy and bypass grafting were followed for periods up to 4 1/2 years (mean, 15 months). The early mortality was 2.9% and the late mortality 3.8%; all of these deaths occurred in patients operated on for heart failure. The survival rate, presented in an actuarial manner, was 91% for the whole group at 3 years. Perioperative infarction occurred in 5.8%, was usually accompanied by patent grafts, and produced left ventricular dysfunction in only 1 of 5 patients investigated. Symptomatic improvement was observed in 96% of the patients. There was fairly good correlation between symptomatic improvement and graft patency. Repeat graft and coronary angiography showed that of 65 grafts to endartectomized arteries, 56 were patent (a patency rate of 87%); there was no evidence of decrease of patency rate with time, and no significant difference between patency rates of grafts to different arteries. The runoff of patent grafts was judged to be good in 75% of patients, moderate in 15% and poor in 10%.