Obliterations of the proximal subclavian artery: to bypass or to anastomose?

A clinical series has been analysed to determine which of two similar, extrathoracic "extraanatomic" methods of treating proximal blocks of the subclavian artery is the superior option. From 1975 until 1988 direct carotid-subclavian anastomosis was used in 32 patients and carotid-subclavian bypass in 19. There were no statistically significant differences for the probability of postoperative survival (p less than 0.877 Breslow; p less than 0.774 Mantel), intraoperative blood loss or the duration of anaesthesia. Those patients who had undergone subclavian artery repair had a significantly longer survival than those following carotid bifurcation endarterectomy (p less than 0.002 Breslow, p less than 0.0002 Mantel). As patients with subclavian lesions have a reasonable life-expectancy, they may possibly experience late complications of their vascular repair. Therefore it seems important to select the most durable operation, and direct carotid subclavian anastomosis has a significantly greater patency rate than bypass (p less than 0.006 Breslow, p less than 0.006 Mantel). Patients with preoperative symptoms of cerebrovascular insufficiency had a lower probability of survival than those with upper extremity claudication, although this did not reach statistical significance (p less than 0.205 Breslow; p less than 0.198 Mantel).