Critical decision analysis for extracranial cerebrovascular disease.

Results from 6 major prospective studies that have recently been either completed, or terminated prematurely, provide compelling evidence of the benefit of carotid endarterectomy in treating certain groups of patients who have carotid stenosis. Results of these studies show that symptomatic patients (those experiencing transient ischemic attack, amaurosis, or completed mild stroke) with a 70% ipsilateral carotid stenosis have an absolute risk reduction of 39% to 65% for stroke or death when treated with carotid endarterectomy as opposed to medical therapy alone. Asymptomatic patients with a 60% ipsilateral carotid stenosis have 53% absolute risk reduction for stroke or death when treated with carotid endarterectomy, rather than medical therapy alone. Combined neurologic morbidity and perioperative mortality rates for treating carotid stenosis should not exceed 3% in the asymptomatic patient or 5% to 7% in the symptomatic patient, on the basis of criteria established by the American Heart Association. These studies show that prophylactic carotid endarterectomy can effectively reduce the risk of stroke in both asymptomatic and symptomatic patients. Centers specializing in vascular surgery can benefit patients by minimizing the operative risk to levels well below those established by the American Heart Association.