Abstract 81: Recurrent Stroke Risk After Angioplasty and Stenting for Symptomatic Intracranial Stenosis: Data From the SAMMPRIS Trial

Purpose: To investigate the incidence and clinical characteristics of recurrent stroke beyond 30 days after uncomplicated angioplasty and stenting for symptomatic intracranial stenosis. Methods: Primary endpoints in SAMMPRIS (Stenting and Aggressive Medical Management for the Prevention of Recurrent Ischemic Stroke) after 30 days past enrollment were defined as ischemic stroke in the territory or any stroke or death within 30 days of a subsequent revascularization procedure. Endpoints were independently and blindly adjudicated. Study records and imaging studies of subjects randomized to the stent arm with post-30 day primary endpoints were reviewed. Instent restenosis (ISR) was categorized as severe (>70%), moderate (50-69%) or mild (< 50%) based on consensus of two reviewers. Findings were categorized as definite, probable, or indeterminate based on imaging modality and study quality. Results: 224 subjects were randomized to the stent arm and 33 suffered a primary endpoint within 30 days of enrollment. Nineteen of the remaining 191 subjects (9.9%) suffered a primary endpoint during follow up (median follow up of 32.4 months). Eighteen had an ischemic stroke in the territory and one had a symptomatic intracranial hemorrhage after repeat angioplasty for in stent restenosis (ISR). In the 18 patients with ischemic stroke, the vascular imaging findings were: complete stent occlusion in 2 (1 of these was acutely revascularized and severe underlying ISR was identified), severe ISR by catheter angiography in 5, severe ISR or occlusion by computed tomographic angiography (CTA) in 1, probable ISR by CTA or magnetic resonance angiography (MRA) in 3, moderate stenosis on angiography in 2 (1 with ISR and 1 with a residual stenosis), indeterminate in 2, normal in 2, and not done in 1. Lesion locations included: distal internal carotid (6), petrous carotid (1), basilar (5), middle cerebral (6), and vertebral (1) arteries. Median time to recurrent stroke was 7.7 months from enrollment (2.2 to 28.2 months). Conclusions: The incidence of recurrent stroke beyond 30 days after uncomplicated angioplasty and stenting in the SAMMPRIS trial was nearly 10% over a mean follow-up of almost 3 years. In stent restenosis was associated with the majority of recurrent strokes.