Risk of Recurrent Stroke before Carotid Endarterectomy: The ANSYSCAP Study

Abstract

BACKGROUND: Carotid endarterectomy yields greater risk reduction for ipsilateral ischemic stroke when performed within two-weeks of the last cerebrovascular symptom than when performed two-weeks or more after the last symptom. However, additional benefit might be gained if carotid endarterectomy is performed earlier than within two-weeks. AIMS: To investigate the 90-day risk of ipsilateral ischemic stroke recurrence after amaurosis fugax, retinal artery occlusion, transient ischemic attack, or minor ischemic stroke in patients with 50-99% carotid stenosis before carotid endarterectomy, with emphasis on the first 14 days. METHODS: Prospective cohort study. 230 consecutive patients with symptomatic 50-99% carotid stenosis (North American Symptomatic Carotid Endarterectomy Trial grading method) who underwent evaluation before carotid endarterectomy. Of these, 183 underwent carotid endarterectomy; the median delay to carotid endarterectomy was 29 days. Blood pressure lowering medication was used by 93% and lipid-lowering medication by 90%. RESULTS: The risk of ipsilateral ischemic stroke recurrence before carotid endarterectomy was 5·2% (n = 12) within two-days, 7·9% (n = 18) within seven-days, 11·2% (n = 25) within 14 days, and 18·6% (n = 33) within 90 days of the presenting event. The risk of ipsilateral ischemic stroke recurrence was higher if the presenting event was a stroke (adjusted hazard ratio 12·4, P = 0·015) or transient ischemic attack (adjusted hazard ratio 10·2, P = 0·026) compared with an amaurosis fugax. DISCUSSION: The risk of recurrent ipsilateral ischemic stroke was high within the first days of the presenting event. Many recurrences would likely have been avoided if carotid endarterectomy had been performed within the first days of the presenting event.