Results of carotid endarterectomy in patients with contralateral internal carotid artery occlusion from the Mid-America Vascular Study Group and the Society for Vascular Surgery Vascular Quality Initiative

Objective: Carotid endarterectomy (CEA) is among the most commonly performed vascular procedures. Some have suggested worse outcomes with contralateral internal carotid artery (ICA) occlusion. We compared patients with and patients without contralateral ICA occlusion using the Society for Vascular Surgery Vascular Quality Initiative database. Methods: Deidentified data were obtained from the Vascular Quality Initiative. Patients with prior ipsilateral or contralateral CEA, carotid stenting, combined CEA and coronary artery bypass graft, or <1-year follow-up were excluded, yielding 1737 patients with and 45,179 patients without contralateral ICA occlusion. Groups were compared with univariate tests, and differences identified in univariate testing were entered into multivariate models to identify independent predictors of outcomes and in particular whether contralateral ICA occlusion is an independent predictor of outcomes. Results: Patients with contralateral ICA occlusion were younger and more likely to be smokers; they were more likely to have chronic obstructive pulmonary disease, preoperative neurologic symptoms (56% vs 47%), nonelective CEA (16% vs 13%), and shunt placement (75% vs 53%; all P <.001). The 30-day ipsilateral stroke risk was 1.3% with vs 0.7% without contralateral ICA occlusion (P =.004). The 30-day and 1-year survival estimates were 99.0% ± 0.5% and 94.1% ± 1.1% with vs 99.6% ± 0.1% and 96.0% ± 0.2% without contralateral ICA occlusion (log-rank, P <.001). Logistic regression analysis identified prior neurologic event (P =.046), nonelective surgery (P =.047), absence of coronary artery disease (P =.035), and preoperative angiotensin-converting enzyme inhibitor use (P =.029) to be associated with 30-day ipsilateral stroke risk, but contralateral ICA occlusion remained an independent predictor in that model (odds ratio, 2.29; P =.026). However, after adjustment for other factors (Cox proportional hazards), risk of ipsilateral stroke (including perioperative) during follow-up was not significantly greater with contralateral ICA occlusion (hazard ratio, 1.21; P =.32). Results comparing propensity score-matched cohorts mirrored those from the larger data set. Conclusions: This study demonstrates likely clinically insignificant differences in early stroke or death in comparing CEA patients with and those without contralateral ICA occlusion. After adjustment for other factors, contralateral ICA occlusion was not associated with a greater risk of ipsilateral stroke (including perioperative) in longer follow-up. Mortality was greater with contralateral ICA occlusion, and this difference was more pronounced at 1 year despite younger age of the contralateral ICA occlusion group. CEA risk remains low even in the presence of contralateral ICA occlusion and appears to be explained at least in part by other factors. CEA should still be considered appropriate in the face of contralateral ICA occlusion.