The elevated stroke/death rates among asymptomatic patients undergoing carotid stenting in the Pacific Northwest are associated with high-risk patient selection.

Objective: Current guidelines recommend treatment of patients with asymptomatic carotid stenosis when stroke/death rates less than 3% can be achieved. However, in the Pacific Northwest region of the Vascular Quality Initiative, elevated stroke/death rates have been reported. This study aims to characterize regional and center-specific outcomes for transcarotid artery revascularization (TCAR) and transfemoral carotid artery stenting (TF-CAS) and investigate potential underlying drivers.

Methods: A retrospective review of asymptomatic patients undergoing TCAR and TF-CAS in the Vascular Quality Initiative for the Pacific Northwest region from 2016 to 2022 was performed. The primary outcome was the composite of stroke or death within 30 days of index hospitalization. Overall regional outcomes and center-specific outcomes were assessed. A high stroke/death rate was defined as greater than 3%. Demographics, comorbidities, and operative risk factors were then compared between centers with high and low stroke/death rates.

Results: A total of 1154 asymptomatic patients across 27 centers underwent carotid stenting in the Pacific Northwest from 2016 to 2022, of which 886 (76.8%) underwent TCAR and 268 (23.2%) underwent TF-CAS. The overall stroke/death rates were 2.5% and 3.0% for TCAR and TF-CAS, respectively. Among centers with stroke/death rates above 3%, for both TCAR and TF-CAS, all were in the top one-half of centers by volume. When patients undergoing TCAR were assessed, those treated at centers with high stroke/death rate underwent revascularization at higher volume centers (12 vs 7 cases per year; P = .03), which treated fewer patients with >80% stenosis (42.1% vs 52.2%; P < .01) and more patients with high-risk anatomy (42.3% vs 35.3%; P = .01), and high-risk physiology as defined by an American Society of Anesthesiologists (ASA) class of 4 or 5 (25.5% vs 17.5%; P < .01). Among patients undergoing TF-CAS, those treated at centers with a high stroke/death rate were more likely to have high-risk anatomy (63.5% vs 48.6%; P = .03), and high-risk physiology as defined by an ASA class of 4 or 5 (23.5% vs 10.4%; P < .01).

Conclusions: High stroke/death rates in the Pacific Northwest appear to be driven by the selection of high-risk patients with less than 80% stenosis. Decreasing the frequency of carotid revascularization in asymptomatic patients with very high physiologic risk including those with ASA class 4 and those with less than 80% stenosis may offer the opportunity for improved outcomes.