MULTICENTER REVIEW OF PREOPERATIVE RISK-FACTORS FOR ENDARTERECTOMY FOR ASYMPTOMATIC CAROTID-ARTERY STENOSIS

Background and Purpose-The benefit of carotid endarterectomy is highly dependent on surgical risk. However, little data are available concer ning factors affecting the risk of endarterectomy performed for asympt omatic carotid artery stenosis outside the setting of a randomized con trolled trial. The purpose of this study was to analyze the impact of potential preoperative risk factors on the frequency of postoperative complications in patients undergoing the operation for asymptomatic di sease in academic medical centers, Methods-Data regarding postoperativ e complications were systematically abstracted from the medical record s of a random sample of patients who underwent carotid endarterectomy at 12 academic medical centers, Results-Of 1160 procedures reviewed, 4 63 (40%) were performed for asymptomatic disease. Postoperative stroke or death occurred in 13 (2.8%), and myocardial infarction occurred in 8 (1.7%). The rate of postoperative stroke or death was lower in asym ptomatic patients than in those with a history of cerebrovascular symp toms in a different vascular distribution, but the difference was not significant (1.8% versus 4.2%; P=.21), Then were no significant differ ences in these rates based on race, a history of angina, recent myocar dial infarction, chronic obstructive pulmonary disease, hypertension, the degree of stenosis of the contralateral or ipsilateral carotid art ery, or the presence of angiographically recognized ulceration, intral uminal thrombus, or siphon stenosis in the ipsilateral vessel (chi(2); P>.05), Postoperative stroke or death was more frequent in women (5.3 % versus 1.6% in men; P=.02), in those aged 75 years or older (7.8% ve rsus 1.8% in those younger than 75 years; P=.01), and in those with a history of congestive heart failure (8.6% versus 2.3% in those without a history of congestive heart failure; P=.03). The risk of stroke or death was higher in the 16 patients who had carotid endarterectomy per formed in combination with coronary artery bypass surgery than in thos e who had only endarterectomy (18.7% versus 2.1%; P<.001). Conclusions -The overall risk of postoperative stroke or death was nearly twice th at reported by Asymptomatic Carotid Atherosclerosis Study (ACAS) inves tigators in the setting of a clinical trial but was within acceptable guidelines. Women were at higher postoperative risk than men, which su pported ACAS findings, Additional high-risk groups were those aged 75 years or older, those with a history of congestive heart failure, and those undergoing prophylactic endarterectomy for asymptomatic stenosis in combination with coronary surgery. Knowledge of these rates may he lp to better assess an individual's postoperative risk and therefore t he anticipated benefit of surgery.