Background: Several clinical trials regarding carotid endarterectomy for asymptomatic stenosis have been conducted in the past two decades. These research studies have not resolved the controversy regarding the optimal treatment of patients with this condition. Summary of review: We examine some of the reasons why there is persisting uncertainty regarding the value of carotid endarterectomy for asymptomatic stenosis. These include the sample size of earlier studies, the generalizability of these studies, and the clinical importance of the reported surgical benefits in some studies. We then review the rationale for another, larger clinical trial. Conclusions: The role of endarterectomy for asymptomatic stenosis remains an unsettled issue. A larger clinical trial may shed light on how to best identify which patients derive clinically significant benefits from prophylactic carotid artery surgery.

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