Urgency of Carotid Endarterectomy for Secondary Stroke Prevention

Abstract

Background and Purpose— The benefit of carotid endarterectomy for preventing recurrent stroke is maximal when surgery is performed within 2 weeks after ischemic stroke or transient ischemic attack; the benefit is reduced when surgery is delayed >2 weeks and essentially lost if delayed >3 months. Guidelines recommend endarterectomy within 2 weeks poststroke/transient ischemic attack for patients with symptomatic carotid stenosis. This study examined time to endarterectomy at designated stroke centers as a measure of evidence-based best practices for stroke prevention. Methods— From the Registry of the Canadian Stroke Network, we identified all consecutive patients presenting with acute ischemic stroke or transient ischemic attack at 12 provincial stroke centers (Ontario, Canada, 2003 to 2006) and selected those with unilateral symptomatic carotid stenosis of moderate (50% to 69%) or severe (70% to 99%) degree. Using linkages to administrative databases, we identified patients who underwent carotid endarterectomy within 6 months after the symptomatic event and calculated the time intervals between the index event and surgery. We compared the timing of surgery according to age, sex, degree of stenosis, index event, geographic region, and year. Logistic regression assessed variables associated with early surgery. Results— One hundred five patients underwent endarterectomy for unilateral symptomatic carotid stenosis (50% to 99%) within 6 months of the index event. The median time from index event to surgery was 30 days (interquartile range, 10 to 81). Only one third (38 of 105) received endarterectomy within the recommended 2-week target timeframe, and in one fourth (26 of 105), surgery was delayed >3 months. Surgery within 2 weeks was more likely if the index event was a transient ischemic attack rather than a stroke. Access to early endarterectomy varied markedly between hospitals across the province and improved over time from 2003 to 2006. Conclusions— In this hospital-based cohort, the majority of patients undergoing carotid endarterectomy after a transient ischemic attack or stroke had surgery delayed well beyond the period of maximum effectiveness. To enhance secondary stroke prevention, greater efforts are needed to minimize delays to diagnosis and surgical treatment for patients with symptomatic carotid stenosis.