Rationale and status of randomized controlled clinical trials in carotid artery stenting.

Efficacy for carotid artery stenting (CAS) has not been confirmed by randomized clinical trial methodology. Although carotid endarterectomy (CEA) is considered the preferred method for carotid revascularization in the management of patients with asymptomatic and symptomatic extracranial carotid occlusive disease, comparisons between CAS and CEA are now underway. In North America, the CREST (Carotid Revascularization Endarterectomy versus Stent Trial) protocol is now completing credentialing cases as randomization of cases is initiated. In Europe, the CAVATAS (Carotid and Vertebral Artery Transluminal Angioplasty Study) and SPACE (Stent Protected Angioplasty versus Carotid Endarterectomy) trials are recruiting symptomatic patients for randomization between CEA and CAS. It is anticipated that these trials will publish definitive results within the next 1-3 years and help guide the referral of patients for CAS and CEA in the future.