The study included 28 patients (14 in each treatment group); the average age was 67 +/- 9.9 years. Men constituted 68% of the patients. After a mean follow-up of 23.1 +/- 10.9 months, there were no recurrences of CI in both groups. No endpoint was reported in the aspirin group, but 2 patients in the OA group (14.3%) exhibited vascular events: 1 acute myocardial infarct and 1 intracerebral hemorrhage). However, this difference was not statistically significant (p = 0.48).Our study suggests that aspirin is the treatment of choice for the prevention of vascular events in patients with symptomatic MCA stenosis.