Carotid artery stenosis for screening for carotid artery stenosis depends on whether someone is experiencing symptoms arising from the stenosis or has risk factors for the development of carotid artery disease. The U.S. Preventive Services Task Force (USPSTF) recommends against routine screening for carotid artery stenosis in those without symptoms. While routine population screening is not advised, the American Heart Association recommends screening for people who don’t have symptoms of carotid stenosis but have been diagnosed with related medical conditions or have risk factors for carotid artery disease. Screening is recommended for people who have: The American Heart Association also recommends screening if
Carotid endarterectomy (CTA) or invasive angiography. Revascularization of symptomatic stenoses has a much higher therapeutic index compared to asymptomatic lesions. The North American Symptomatic Carotid Endarterectomy Trial (NASCET) and the European Carotid Surgery Trial (ECST) are both large randomized class 1 studies which have helped define current indications for carotid endarterectomy in symptomatic patients. The NASCET found that for every six patients treated, one major stroke would be prevented at two years (i.e. a number needed to treat (NNT) of six) for symptomatic patients with a 70–99% stenosis, where percent stenosis was defined as: Symptomatic patients with less severe carotid occlusion (50–69%)