Editorial: Carotid Revasculatization vs Best Medical Management in Symptomatic Carotid Artery Disease

Over the last two decades, the North American Symptomatic Carotid Endarterectomy Trial (NASCET) has been a game changer in the management of symptomatic carotid artery disease. The study demonstrated a 17% absolute risk reduction (ARR) in reducing recurrent stroke in patients with symptomatic carotid disease who underwent carotid endarterectomy (CEA) compared to best medical management, mainly aspirin and risk factor reduction. There was also an observed reduction in fatal or major strokes in the (CEA) group versus medical therapy (2.5% vs. 13.1%), less benefit was seen in the 50%–69% stenosis group.[1] Similar results were replicated in the European Carotid Surgery Trial (ECST) with benefit being seen as ARR of 11.6% in patients with symptomatic carotid arterial disease and prior minor stroke or transient ischemic attack (TIA).[2] Since the two studies used different imaging criteria, reanalysis of ECST based on the NASCET criteria revealed very similar benefits, namely, mild risk reduction with stenosis of 50%–69% (5.7%) and highly significant risk reduction in the 70%–99% group (21.2%), with no benefit in the near occlusion group.[3] Subsequent studies comparing CEA to carotid stenting (CS) (The Carotid Revascularization Endarterectomy vs. Stenting Trial [CREST]) and Medical Management for asymptomatic carotid stenosis demonstrated that both stenting and CEA were equally effective with younger patients benefiting more from CS versus older patients where CEA seemed more effective. This has led to the guideline recommendations that patients with symptomatic carotid stenosis should be offered CEA or CS.[4]

Medical management of large artery atherosclerosis-related stroke management underwent a dramatic change with wider implementation of risk factor reduction strategies and introduction of HMG-CoA Reductase Inhibitors (statins), nonexistent at the time of the NASCET or ECST trials. Statins reduce the recurrence risk after a stroke or TIA as well as improve stroke outcomes. In the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL), patients with prior TIA or stroke without known ischemic heart disease were randomized to receive atorvastatin 80 mg versus placebo and followed for almost 5 years with an ARR for recurrent events of 3.5% and a trend toward better outcomes.[5] This trial mirrors our own experience demonstrating improved stroke outcome in acute ischemic stroke in patients on statins prior to or after stroke onset.[6]

The overall rate of CEA has been dropping since the last decade, by approximately 6%, counterbalanced by a slight increase in CS after CREST.[7]

Stenting versus Aggressive Medical Therapy for Intracranial Arterial Stenosis (SAMMPRIS) further raises the question whether best medical therapy may be a better option as was seen in SAMMPRIS with symptomatic intracranial stenosis.[4]

In this issue, the investigators at a large university teaching hospital in Hyderabad, India, report the results of best medical therapy (vascular risk factor reduction, high-dose statins, dual antiplatelet therapy for 3 months and blood pressure reduction to <140/90 mmHg versus carotid intervention in symptomatic carotid artery disease. This small observational study demonstrated no difference in outcomes between patients treated with CEA/CS versus best medical treatment. Results were similar in moderate and severe carotid stenosis.[8] While this is not a randomized controlled trial (RCT), it offers a tentative hint that maybe the SAMMRIS results can be replicated in patients with extracranial arterial stenosis and appeals for a RCT to confirm or refute these important findings. Hopefully CREST-2, an ongoing study to assess best medical management against CEA or CS may provide the much-needed answers.[9]