Best Medical Therapy for Asymptomatic Carotid Stenosis: Imminent or Ineffective?

Abstract

Carotid artery disease accounts for approximately 20% of all ischemic strokes, a major cause of morbidity, and the fifth leading cause of death in United States. Landmark trials in the 1990s such as Asymptomatic Carotid Atherosclerosis Study (ACAS) and Asymptomatic Carotid Surgery Trial (ACST) establish carotid endarterectomy (CEA) plus best medical therapy (BMT) as the standard of care for patients with asymptomatic carotid stenosis over 60%. However, advances in medical therapy and the emergence of carotid artery stenting (CAS) have prompted a reevaluation of treatment efficacy. Recent studies have questioned the superiority of CEA over BMT alone in reducing stroke risk, suggesting no significant difference in outcomes with contemporary medical management. Additionally, analysis from the US Department of Veterans Affairs indicated minimal net benefit of CEA over BMT when accounting for all-cause mortality. Comparative studies have found no significant difference in long-term stroke free survival between CEA and CAS. However, procedural risks vary, with higher myocardial infarction rates associated with CEA and higher stroke rates with CAS. Identifying high-risk plaques and patient-specific risk factors remains crucial. Meta-analyses have highlighted features such as neovascularization and lipid rich cores as predictors of stenosis progression and ischemic events. Ongoing research, particularly the CREST-2 trial, aims to provide clear guidance on the optimal treatment of asymptomatic carotid stenosis. This trial emphasizes stringent adherence to modern BMT protocols and includes comprehensive lifestyle modification programs. The evolving landscape of medical and surgical interventions necessitates continuous evaluation to optimize treatment strategies for asymptomatic carotid stenosis, which is the impetus for this review. Future findings from ongoing trials are expected to refine current guidelines and improve patient outcomes.