High Stroke Rate in Patients With Medically Managed Asymptomatic Carotid Stenosis at an Academic Center in the Southeastern United States

Background

Although the publication of randomized clinical trials defining the benefit of carotid endarterectomy (CEA) for asymptomatic carotid stenosis, medical management of carotid stenosis has changed significantly. With antiplatelet agents and statins, some question whether these trials are still relevant, suggesting that asymptomatic patients with >70% internal carotid artery (ICA) stenosis may do better with medial management alone, lessening the need for CEA and carotid stenting. The Vascular Quality Initiative (VQI) registry has shown that there are wide practice variations regarding the degree of stenosis that prompts surgical intervention but there are few reports of outcomes in patients who do not undergo intervention. We sought to determine the clinical outcomes of the >70% carotid stenosis patients who are treated with medical management alone at our institution.

Methods

We identified all patients with ICA stenosis >70% based on hemodynamic consensus criteria (peak systolic velocity >230 cm/s) in our peripheral vascular laboratory from January 2013 through December 2016. With a retrospective chart review, demographics, comorbid conditions, medications, radiographic studies, clinical follow-up, interventions, and outcomes at 2 years were included. Descriptive statistics were used to define these variables.

Results

One hundred and seventy three patients were identified with medically managed asymptomatic >70% ICA stenosis based on hemodynamic criteria on duplex ultrasound. The mean age was 67.5 years, 49% were male, 64% were White, 14% were Black, 13% race was undisclosed, 89% were prescribed antiplatelet therapy, 85% were prescribed a statin, and 60% had hypertension controlled to <140/90. Twenty patients (11.5%) experienced a cerebrovascular event during the 2-year study period. There were eight patients with transient ischemic attack, 10 with ipsilateral strokes, and 2 with strokes in unrelated territories.

Conclusions

Despite good adherence to current recommendations for medical therapy, patients at our institution are developing symptomatic carotid disease at a rate similar to that reported in historical clinical trials. These data supports the concept that advances in medical management have not resulted in reduced stroke rates in asymptomatic patients with high-grade carotid stenosis at a large academic institution located in the southeastern United States. CEA and stenting provide a significant risk reduction and should be considered more often in this patient population.