LAUSR

INTRODUCTION Atypical fibromuscular dysplasia (AFMD), also known as carotid web, is a rare underdiagnosed shelf-like fibrous tissue arising from the posterior carotid artery bulb that is a cause of cryptogenic stroke of the anterior cerebral vascularization. Despite the recurrence and severity of strokes caused by embolization associated with AFMD, there are no recommendations on the best strategy to manage single and bilateral lesions, which have unsatisfactory outcomes when treated with medical treatment exclusively. METHODS From January 2016 to April 2019, 365 patients were operated on for a carotid stenosis in our institution. This cohort included 11 patients (3%), with a median age of 41 years (39-51 years), referred by a stroke unit, treated for a symptomatic (10 strokes and 1 recurrent TIA) AFMD lesion. Pre-operative workup revealed a contralateral similar lesion in 45 % of patients (5/11), which all also underwent surgery during a subsequent hospitalization. The diagnosis was confirmed by histological examination when open surgery was performed. 30-day and 1-year outcomes were retrospectively reviewed. RESULTS Of the 16 AFMD lesions operated: 13 were treated by open surgery (2 by classic endarterectomy and 11 by internal carotid resection-anastomosis) and 3 by carotid artery stenting, respectively with a mean delay of 85.5 days and 20.5 days following the lastest stroke. There was one complication following stenting (external iliac rupture) that was treated by a covered stent, and no peri operative complication following open surgery. The follow-up at 30 days and one year was uneventful for all patients, without any deaths nor stroke recurrences. CONCLUSION Symptomatic AFMD is a rare cause of cryptogenic stroke. Bilateral lesions are frequent. Early intervention is associated with favorable peri operative and one-year outcomes. Open surgery is the first line therapeutic option in this young patient population.