Impact of contralateral carotid or vertebral artery occlusion in patients undergoing carotid endarterectomy or carotid artery stenting

Objective: To determine the impact of contralateral carotid occlusion (CCO) and/or vertebral artery occlusion (VAO) on the development of early postoperative neurologic complications after carotid endarterectomy (CEA) or carotid artery stenting (CAS). Methods: A retrospective analysis was conducted using a database of patients who underwent CEA (n = 698) or CAS (n = 455) at a single institution. Excluded were 44 CEAs synchronously performed with coronary artery bypass grafting and 76 CASs performed without an embolic protective device (n = 69) or that resulted in technical failures (n = 7). All CEAs were the conventional type and performed under general anesthesia, and carotid shunts were routinely used. Patients were categorized into three groups according to patency of the contralateral carotid and vertebral arteries: Group I (no CCO or VAO); Group II (CCO with or without VAO); Group III (with VAO but no CCO). CCO or VAO were diagnosed with two or more carotid imaging studies including duplex ultrasonography, computed tomography angiography, magnetic resonance angiography, or conventional carotid angiography. Patient groups were compared with demographics, preoperative symptomatic status, and frequencies of early (<30 days) symptomatic neurologic complications (ESNCs) including transient ischemic attack and stroke. Postprocedural stroke alone was separately compared. Univariate (chi(2) or Fisher's exact test) and multivariate analysis (multiple logistic regression) were conducted to determine predictors of ESNC or postprocedural stroke. Results: ESNCs and postprocedural stroke developed significantly more often with CAS compared with CEA (ESNC, 2.6% vs 8.1%; P < .001; stroke, 1.3% vs 6.8%; P < .001). In group II, the frequency of ESNCs was higher (6.8% vs 1.8%; P = .044), but the frequency of postprocedural stroke was not significantly higher (2.3% vs 0.9%; P = .405) in the CEA group. By multivariate analysis, the presenting symptom of stroke (odds ratio, 3.612; 95% confidence interval, 1.288-10.130; P = .015) and group II (odds ratio, 7.242; 95% confidence interval, 1.727-30.374; P = .007) were independent risk factors of ESNC following CEA but not CAS. When we analyzed the risk factor for postprocedural stroke alone, the presenting symptom of stroke was the only risk factor, while presence of CCO or VAO was not. Conclusions: CAS was followed by a significantly higher frequency of ESNC and postprocedural stroke compared with CEA. By subgroup analysis, CCO was a risk factor for ESNC but not for postprocedural stroke alone in patients undergoing CEA. Unilateral or bilateral VAO was not associated with a higher rate of ESNC or stroke in CEA or CAS.