Does low-dose acetylsalicylic acid prevent stroke after carotid surgery?: A double-blind, placebo-controlled randomized trial

Abstract

Background and Purpose: The aim of this randomized double-blind, placebo-controlled trial was to evaluate whether neurological deficits could be prevented with low-dose acetylsalicylic acid (ASA) as an adjunct to carotid endarterectomy. Methods: A total of 232 patients were randomized to two groups, 75 mg/d ASA starting preoperatively and continued for 6 months (n=117) or placebo (identical tablets) (n=115). The patients were followed up regularly for 1 year. Results: The groups were well matched regarding laboratory data and indication for operation. The number of patients with intraoperative or postoperative stroke without complete recovery within 1 week were 0 and 2 at 30 days and 6 months, respectively, in the ASA group, compared with 7 and 11 in the placebo group (P=.01). Including all neurological events within 6 months, this was found in 15 patients in the ASA group compared with 24 in the placebo group (P=.12). Mortality was 0.8% and 3.4% at 30 days and 6 months, respectively, in the ASA group. In the placebo group, the corresponding figures were 4.3% and 6.0o, respectively (P=.12). The intraoperative bleeding did not differ between the groups nor did the number of reoperations due to bleeding or other complications related to pharmacology. Conclusions: This study indicates that low-dose ASA (75 mg/d) reduces the number of postoperative strokes without complete recovery within 1 week. Overall neurological events are insignificantly reduced, as also mortality. The use of low-dose ASA (75 mg) seems safe and effective in reducing cerebrovascular events after carotid endarterectomy. © 1993, Stroke. All rights reserved.