Who should be screened for asymptomatic carotid artery stenosis?

Interest in screening for extracranial CAS has increased after the publication of studies demonstrating that carotid endarterectomy (CEA) can prevent stroke in asymptomatic patients with extracranial carotid disease.1-3 The interest in screening has grown further with the addition of carotid artery stenting to the armamentarium of carotid revascularization.4 The benefit of screening, namely stroke prevention, depends on several factors: the prevalence of asymptomatic CAS in specific populations; the natural history of carotid disease; the sensitivity and specificity of the screening method (most often, duplex ultrasono graphy); the need to confirm the diagnosis (magnetic resonance arteriography [MRA], computed tomographic angiography [CTA], contrast arteriography); the costs of screening; and the costeffectiveness of carotid revas cularization (CEA vs carotid stenting). It is essential to recognize that all studies that addressed this topic constructed decision-making models to test the cost-effectiveness of screening individuals for asymptomatic CAS to identify candidates for CEA. It cannot be presumed that these models would apply to individuals with asymptomatic CAS who are candidates for carotid artery stent revascularization.