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 (