Recurrent Hemispheric Stroke Syndromes in Symptomatic Atherosclerotic Internal Carotid Artery Occlusions: The Carotid Occlusion Surgery Study Randomized Trial

BACKGROUND: There are limited data on outcomes of extracranial-intracranial (EC-IC) bypass in patients with recurrent hemispheric syndromes due to atherosclerotic internal carotid artery occlusion (AICAO). OBJECTIVE: To compare clinical outcomes and efficacy of EC-IC bypass surgery in patients with and without recurrent hemispheric syndromes associated with AICAO in the Carotid Occlusion Surgery Study (COSS). METHODS: In patients enrolled in the COSS trial, we compared baseline characteristics and clinical outcomes for participants with (rHEMI+) and without recurrent hemispheric ischemia (rHEMI−) prior to randomization into surgical vs medical groups. The primary outcome was all stroke and death from randomization through 30 d and ipsilateral ischemic stroke within 2 yr. RESULTS: Of 195 randomized participants, 100 were rHEMI+ (50 in each group). Baseline characteristics between rHEMI+ and rHEMI− participants were similar except rHEMI+ were more likely to have had previous stroke prior to randomization (61% vs 20%, P