Abstract Number: Esoc2026a1805 Endovascular Therapy Versus Medical Management for Large Ischemic Core Stroke Identified at Primary Stroke Centers: A Subanalysis of the Laste Trial

Abstract Background and aims In acute ischemic stroke due to large-vessel occlusion (AIS-LVO) with a large ischemic core identified at primary stroke centers (PSC) -without rapid access to endovascular therapy (EVT)-, it remains uncertain whether EVT improves functional outcomes over medical management (MM). Methods We performed a post-hoc analysis of the LASTE randomized controlled trial, which compared MM plus EVT and MM alone in anterior circulation AIS-LVO patients with a large ischemic core (ASPECTS 0-5) treated within 6.5 hours of last seen well. This analysis included patients whose baseline imaging was obtained at a PSC and already demonstrated an ASPECTS of 0-5, before inter-hospital transfer. The primary outcome was functional outcome at 3 months, assessed using the modified Rankin Scale (mRS). Results Among the 333 patients enrolled in LASTE, 157 were included in this analysis; 80 received MM alone and 77 underwent EVT plus MM. Median age was 73 years, NIHSS score 20, and symptoms onset-to-PSC imaging time 120 minutes. PSC imaging was MRI in 99% of cases, showing ASPECTS 0-2 in 56% and 3-5 in 44%. Median time from PSC imaging to comprehensive center admission was 145 minutes. EVT resulted in better functional outcomes than MM alone (generalized odds ratio, 1.71; 95%CI 1.21-2.41; P = 0.002). Death at 3-month (relative risk, 0.73; 95%CI 0.50-1.05; P = 0.08) and symptomatic hemorrhagic transformation (relative risk, 1.85; 95%CI 0.64-5.26; P = 0.24) was similar across groups. Conclusions These findings support consideration of inter-hospital transfer for EVT in AIS-LVO patients with a large ischemic core admitted in PSC in the early time-window. Conflict of interest The authors have nothing to disclose.