Asymptomatic carotid artery stenosis: a review

The use of carotid endarterectomy (CEA) in the treatment of symptomatic carotid stenosis has become well accepted practice based on the results of the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and the European Carotid Surgery Trial (ECST). Similarly, the Asymptornatic Carotid Atherosclerosis Study (ACAS) and the Asymptornatic Carotid Surgery Trial (ACST) have shown significant risk reduction with CEA in patients with asymptomatic carotid stenosis. Since the results of these studies however, there have been significant advances in medical therapy, surgical technique and less invasive endovascular options for the treatment of carotid stenosis. The Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy (SAPHIRE) trial was able to show the non-inferiority of carotid artery stenting (CAS) to CEA in a subset of high risk patients. Based on this and the results of multiple registries some have extrapolated the benefit of CAS over best medical therapy (BMT) for the treatment of carotid stenosis. Despite the results of these studies, there is still significant debate in the use of CEA and CAS for the treatment of asymptomatic carotid stenosis. In this paper, we will review the major clinical trials and evaluate the three treatment options for asymptomatic carotid stenosis: CEA, CAS, and BMT.