Perioperative and late stroke rates of carotid endarterectomy contralateral to carotid artery occlusion : results from a randomized trial.

Abstract

Several previous studies have reported the benefits of carotid endarterectomy (CEA) contralateral to carotid occlusion with mixed results, but none of these were randomized except for the North American Symptomatic Carotid Endarterectomy Trial. The purpose of this study was to analyze the results of surgery in patients with contralateral carotid artery occlusion in a randomized trial in which randomization was done according to the method of closure. In 399 CEAs (357 patients) that were randomized into primary closure versus patching, 49 had contralateral occlusion. Strokes were designated as ipsilateral if they arose from the same CEA side and contralateral if they arose from the occluded side. A Kaplan-Meier analysis was used to estimate perioperative strokes and stroke-free survival in patients with contralateral occlusion (group A) versus those without contralateral occlusion (group B). Demographic characteristics and mean follow-up for both groups were similar (group A, 40 months; group B, 33 months). Group A had a higher incidence of contralateral transient ischemic attacks (TIAs) (12.2% versus 0.9%; P<0.0001), contralateral strokes (2% versus 0%; P=0.025), and combined contralateral TIAs/strokes (14.3% versus 0.9%; P<0.0001). The rates for perioperative and all strokes (operative and late) were 2% and 4. 1% (2% ipsilateral and 2% contralateral strokes) for group A and 2. 9% and 3.4% (all ipsilateral) for group B (P=0.60 and 0.85, respectively). The rates for perioperative and all TIAs were 0% and 14.3% for group A versus 2.6% and 6.3% for group B (P=0.918 and P=0. 08, respectively). The rates for perioperative and all neurological events (TIA and stroke) were 2% and 18.4% for group A and 5.4% and 9. 7% for group B (P=0.27 and 0.113, respectively). The cumulative stroke-free survival rates at 5 years were 84% for group A and 77% for group B (P>0.1). The cumulative stroke-free survival rates at 5 years for symptomatic and asymptomatic patients in group A and group B were also similar. The perioperative and late deaths were similar for both groups (group A, 8%; group B, 14%). Group A had a higher incidence of contralateral TIAs and strokes than group B; however, the perioperative and all late stroke rates and survival rates of CEA were comparable in patients with and without contralateral occlusion.