Thirty bypass grafts to coronary arteries were made possible by manual core endarterectomy. The overall patency rate of the grafts was 57%, which is less than the patency rate of bypass grafts to nonendarterectomized vessels (75 to 80%). In the perioperative period and during follow-up to 29 months there was no increase in mortality or morbidity even when the endarterectomized vessel subsequently became occluded. These results represent early technical experience. Routine anticoagulant therapy in the postoperative period, to prevent early occlusion, was not used. The results of this and other studies suggest that coronary endarterectomy with bypass grafting is a useful procedure in situations where the coronary artery is so severely obstructed that standard saphenous vein bypass grafting cannot be performed; the procedure is superior to coronary endarterectomy alone.