O08 Medium vessel occlusion aspiration thrombectomy using freeclimb 54 catheter delivered by tenzing 5: early multicenter clinical experience

<h3>Introduction</h3> Medium-vessel occlusions (MeVO) of the M2/3, A2/3, and P2/3 account for 25%–40% of acute ischemic stroke (AIS). The FreeClimb^TM 54 catheter (distal 0.054 inch ID and a 1.7 mm distal OD) is packaged with a specialized delivery catheter, Tenzing^® 5 (Route 92 Medical, San Mateo, CA). <h3>Aim of Study</h3> We report our initial off-label experience using the FreeClimb 54 and Tenzing 5 in MeVO AIS. <h3>Methods</h3> After local IRB approvals, we retrospectively reviewed consecutive patients who underwent off-label MeVO AT with the FreeClimb 54 and Tenzing 5 at 7 institutions from 09/2023-03/2024. <h3>Results</h3> Thirty nine patients were treated, 70 ± 18 years old; 21(54%) of which were female. There were 27(69%) primary MeVO and 12(31%) secondary MeVO. Freeclimb 54 was successfully delivered over Tenzing 5 to the target in 39/39(29 M2, 4 M3, 1 M1, 2 A2, 1 A3, 2 P2). Average target vessel diameter was 1.6±0.3 mm on DSA. No stent-retrievers were used for FreeClimb 54 delivery. A stent-retriever was used for an additional thrombectomy pass (2%). A leading microwire was used to advance the Tenzing in 34/39(87%). Primary MeVO mTICI 2C/3 reperfusion was achieved in 21/27(78%) after a median of 1(IQR 1-1) pass, with first pass effect (2C/3) in 21/27(78%). We observed low grade vasospasm in 7/39(18%); one transient carotid-cavernous fistula; one symptomatic intracranial hemorrhage (1/39, 3%) involving a pass in a 1.0 mm diameter M3 segment. <h3>Conclusion</h3> Initial clinical experience supports access to intracranial MeVO using Tenzing 5 and FreeClimb 54, for rapid and effective reperfusion with low complication rate. <h3>Disclosure of Interest</h3> yes Consultant: Route 92 medical, Stryker; Equity interest: Route 92 Medical.