Clinical Impact of Contralateral Carotid Occlusion in Patients Undergoing Carotid Artery Revascularization

Background: The presence of a contralateral carotid occlusion (CCO) is an established high-risk feature for patients undergoing carotid endarterectomy (CEA) and is traditionally an indication for carotid artery stenting (CAS). Recent observational data have called into question whether CCO remains a high-risk feature for CEA.

Objectives: The purpose of this study was to determine the clinical impact of CCO among patients undergoing CEA and CAS in a contemporary nationwide registry.

Methods: All patients undergoing CEA or CAS from 2007 to 2019 in the NCDR CARE (National Cardiovascular Data Registry Carotid Artery Revascularization and Endarterectomy) and PVI (Peripheral Vascular Intervention) registries were included. The primary exposure was the presence of CCO. The outcome was a composite of in-hospital death, stroke, and myocardial infarction. Multivariable logistic regression and inverse-probability of treatment weighting were used to compare outcomes.

Results: Among 58,423 patients who underwent carotid revascularization, 4,624 (7.9%) had a CCO. Of those, 68.9% (n = 3,185) underwent CAS and 31.1% (n = 1,439) underwent CEA. The average age of patients with CCO was 69.5 ± 9.7 years, 32.6% were women, 92.8% were Caucasian, 51.7% had a prior transient ischemic attack or stroke, and 45.4% presented with symptomatic disease. Over the study period, there was a 41.7% decrease in the prevalence of CCO among patients who underwent carotid revascularization (p < 0.001), but CAS remained the primary revascularization strategy. Unadjusted composite outcome rates were lower in patients with CCO after CAS (2.1%) than CEA (3.6%). Following adjustment, CCO was associated with a 71% increase in the odds of an adverse outcome after CEA (95% confidence interval: 1.27 to 2.30; p < 0.001) compared with no increase after CAS (adjusted odds ratio: 0.94; 95% confidence interval: 0.72 to 1.22; p = 0.64).

Conclusions: CCO remains an important predictor of increased risk among patients undergoing CEA, but not CAS.