Gas endarterectomy with distal bypass of the coronary arteries.

Carbon dioxide gas endarterectomy was first applied in cases of total occlusion of the right coronary artery. The early technique involved removal of the disease core along the entire length of the vessel. At follow-up, progressive changes were observed to cause segmental stenosis within the proximal and middle portions of the vessel which led to complete reocclusion of the artery at 36 months. In every case, however, the distal branches of the endarterectomized arteries appeared unaffected. On the basis of these results, we have modified our technique. The present treatment involves distal endarterectomy with aortocoronary bypass to the endarterectomized segment. This surgical approach is appropriated only in cases of diffuse atherosclerotic involvement of the distal arterial branches. It can be applied to any one of the three main coronary artery branches and has therefore broadened the range of patient selection for direct myocardial revascularization. The operative mortality in our series of 58 patients was 6.9 per cent (4 patients), but all deaths were associated with such aggravating factors as anerurysm formation, valve disease, and the preoperative evolution of myocardial infarction. The associated morbidity rate was 6.8 per cent; two patients had disruption of the sternal wound, and one suffered uncomplicated myocardial infarction. The fourth patient had a myocardial infarction followed by development of conduction defect and required operation for the insertion of a permanent transvenous pacemaker. To date, follow-up indicates a high patency rate among the surviving 54 patients.