Abstract WP181: Treatment of Unruptured Small and Medium Wide-Necked Aneurysms of the Internal Carotid Artery Using the 64-Wire Surpass Evolve: Results of the SEASE International Registry

Introduction: The management of wide-necked internal carotid artery (ICA) aneurysms is technically challenging with established endovascular and microsurgical techniques that are limited by the associated morbidity and/or recurrence. The PREMIER study first demonstrated high rates of complete occlusion without parent vessel stenosis or permanent neurological complications after the treatment of wide-necked small and medium-sized intracranial ICA aneurysms with the 48-wire pipeline. We aimed to assess the effectiveness and safety of the new generation 64-wire Surpass Evolve (SE) flow diverter for the treatment of the same intracranial ICA aneurysm population. Methods: This is a sub-analysis from the Safety and Effectiveness Assessment of the Surpass Evolve (SEASE) registry, an observational cohort study including 15 academic institutions in North America and Europe spanning between 2020-2023. Analysis included patients with unruptured wide-necked saccular aneurysms (not previously treated), measuring <12 mm along the ICA segments. Primary effectiveness was complete occlusion (Raymond Roy Class 1) without retreatment at 1-year follow-up (core lab adjudicated), and primary safety was major stroke (ischemic/hemorrhagic) in the territory supplied by the target artery or death. Results: 129 cases were included (median age 58 years, IQR: 50-67 years, 85% females). Median aneurysm and neck size were 5.8 mm (IQR: 4.0-7.5) and 4.1 (IQR, 3.0-5.5). Most aneurysms were in the ICA C6 segment (66.7%, 86/129), followed by the C7 segment (21.0%, 21/129). Successful implantation was encountered in 99% (128/129) of the cases. At a median 10.1 months (IQR: 6.3-12.6), the rate of complete occlusion was 75.2% (91/121), ≥50% in-stent stenosis 7% (9/129), and retreatment 0.8% (1/129). Major stroke and overall mortality were reported in 1.6% (2/129) of the cases. Conclusion: Our study evaluating outcomes from the SEASE international multicenter registry found that patients with wide-necked unruptured saccular small to medium-sized aneurysms can be effectively treated with the 64-wire chrome-cobalt SE. Furthermore, the SE showed a considerable safety profile for this patient population.