Although the predominant location of symptomatic carotid artery occlusive disease is the carotid bifurcation, proximal common carotid artery lesions cause similar symptoms. Common carotid artery lesions occur as isolated disease or in tandem with carotid bulb disease. Restoration of carotid artery inflow from subclavian based extraanatomic bypasses should provide adequate reconstruction of these lesions. To evaluate subclavian-carotid artery bypass, a retrospective review of all patients undergoing this procedure from Jan. 1, 1977, to Feb. 20, 1989, was performed. Twenty patients (14 men, 6 women) with a mean age of 60 years were treated. Fifteen patients (75%) were admitted with transient ischemic attacks. Five (25%) had nonfocal symptoms (e.g., dizziness, syncope). Arteriographic evaluation demonstrated severe proximal occlusive disease of the common carotid artery in all cases. Reconstruction bypasses were performed to the carotid bulb (45%), internal carotid artery (30%), and external carotid artery (25%). Four patients underwent endarterectomy of the internal carotid artery in conjunction with subclavian-carotid artery bypass. Bypass conduits included saphenous vein (75%) and prosthetic grafts (25%). Asymptomatic phrenic nerve neuropraxia was identified by postoperative chest radiography in four cases, with no resultant respiratory disease. No perioperative strokes occurred. One postoperative death (5%) resulted from a myocardial infarction. Long-term results were available for 18 patients (90%), with a mean follow-up of 50 months (range, 1 to 122 months). Four patients have died of causes unrelated to carotid vascular disease. Serial duplex scans have documented graft patency in all 18 patients. A single patient returned with focal neurologic symptoms as a result of a posterior circulation infarct.(ABSTRACT TRUNCATED AT 250 WORDS)