Revascularization of Asymptomatic High-Grade Stenosis Is Not Indicated With Contemporary Stroke Prevention Medical Therapy

The American Stroke Association Guidelines for Primary Prevention of Stroke state that for patients with asymptomatic carotid artery stenosis, “the advantage of revascularization over current medical therapy alone is not well established.” So, what is the evidence related to the management of asymptomatic high-grade carotid artery stenosis (AHGCAS), and why should we interpret this evidence to conclude that contemporary medical therapy alone is the preferred treatment to reduce ipsilateral stroke risk? Three studies, the Asymptomatic Carotid Atherosclerosis Study (ACAS), the Medical Research Council (MRC) Asymptomatic Carotid Surgery Trial, and the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST), have documented 5-year risks of periprocedural complications and subsequent stroke among patients with AHGCAS treated with revascularization of 5.1%, 6.4%, and 4.6% (estimated), respectively. Conversely, the ACAS and MRC studies documented 5-year risks of stroke for patients with AHGCAS treated with medication alone of 11.0% and 11.8%, resulting in an absolute risk reduction in ipsilateral …