Transfemoral Carotid Artery Stents Should Be Used with Caution in Patients with Asymptomatic Carotid Artery Stenosis.

Background: Significant national variation exists in defining the degree of stenosis that requires intervention in patients with asymptomatic carotid artery stenosis (ACAS). We aimed to evaluate the risk of perioperative and 2-year stroke and death in ACAS patients undergoing carotid endarterectomy (CEA) and carotid artery stenting (CAS) for severe versus very severe stenosis in a contemporary population.

Methods: All patients undergoing CEA or transfemoral CAS for ACAS in the Vascular Quality Initiative (2005-2017) were included. Degree of stenosis was defined as the highest recorded on any imaging method. Univariable and multivariate logistic regression analyses were performed to assess risk of stroke, stroke/death, and major adverse cardiac events (MACE) at 30 days; and Cox proportional hazard, life tables, and Kaplan-Meier estimates were implemented to evaluate ipsilateral stroke and stroke/death at 2 years postoperatively in patients undergoing CEA versus CAS for severe (60-79%) and very severe (≥80%) stenosis adjusting for baseline characteristics.

Results: A total of 53,337 ACAS patients were examined (severe stenosis = 17,586; 33.%), of which 11.5% (n = 6,127) underwent CAS. The crude incidence of 30-day stroke/death was significantly higher for CAS versus CEA in the very severe stenosis group (2.0% vs. 1.2%, P < 0.001), but not in the severe stenosis group (1.7% vs. 1.3%, P = 0.17). MACE was not significantly different for CAS versus CEA in either group (P ≥ 0.64). On multivariable analysis, CAS was associated with a persistently higher risk of 30-day stroke or death compared to CEA in patients with very severe stenosis (odds ratio [OR] 1.64, 95% confidence interval [CI] 1.26-2.13). The 30-day composite stroke/death risk for patients undergoing CEA was similar for severe versus very severe stenosis (OR 1.07, 95% CI 0.89-1.28), but there was a trend toward higher risk of perioperative stroke in the severe stenosis group (OR 1.23, 95% CI 0.97-1.56). Two-year outcomes were similar; the crude annualized incidence rates of stroke and stroke/death were higher for CAS versus CEA in both the severe (stroke: incidence rate ratio [IRR] 1.62, 95% CI 1.00-2.55; stroke/death: IRR 1.53, 95% CI 1.11-1.64) and very severe stenosis (stroke: IRR 1.97, 95% CI 1.44-2.65; stroke/death: IRR 1.51, 95% CI 1.34-1.68) groups (all, P ≤ 0.04). On multivariable Cox proportional hazards analysis, CAS was associated with a higher risk of stroke or death compared to CEA in patients with both severe (hazard ratio [HR] 1.40, 95% CI 1.15-1.70) and very severe stenosis (HR 1.62, 95% CI 1.37-1.90).

Conclusions: More than one-third of patients undergoing carotid revascularization for ACAS had 60-79% stenosis. Having lower degree of stenosis is not protective against stroke and death for either CEA or CAS at either 30 days or 2 years postoperatively. We believe that optimal medical management should be the first line in stroke prevention for asymptomatic patients with severe (60-79%) carotid stenosis.