ABSTRACT NUMBER: ESOC2026A253 THROMBECTOMY FOR ACUTE STROKE DUE TO MEDIUM VESSEL OCCLUSION ACROSS PERFUSION MISMATCH PROFILES: A POST-HOC ANALYSIS OF THE ESCAPE-MEVO TRIAL

Abstract Background and aims Recent trials have shown no benefit of endovascular thrombectomy (EVT) vs. medical therapy in medium vessel occlusion (MeVO) stroke. We aimed to investigate the association between perfusion mismatch profiles and functional outcomes in MeVO stroke and to assess whether these profiles modify the treatment effect of EVT. Methods Post-hoc analysis of patients with available baseline perfusion imaging from ESCAPE-MeVO, a multicenter, randomized trial that investigated the efficacy and safety of EVT plus medical therapy compared to medical therapy alone in patients with acute MeVO stroke. Perfusion mismatch ratio and volume were defined as the ratio and difference between the critically hypoperfused area and the CTP-estimated ischemic core. The primary outcome was 90-day ordinal modified Rankin Scale (mRS). Treatment effect modification was assessed using interaction terms (perfusion mismatch*EVT). Results Of 530 enrolled patients, 309 (58.3%) had available perfusion imaging and were included in this study. Median age was 73 years (IQR = 63-82) and 141 (45.6%) were females. Median perfusion mismatch volume was 37.2 mL (IQR = 22.59 and ratio 6.1 (IQR = 2.8-10.0). Ordinal 90-day mRS was not associated with perfusion mismatch volume (adjusted OR 1.03 [95%CI = 0.99- 1.07]; per each 10-mL increase) or ratio (adjusted OR 1.03 [95%CI = 0.97- 1.09]; per each 1-unit increase). There was no modification of EVT effect by perfusion mismatch volume (p-interaction = 0.620) or ratio (p-interaction = 0.294) on ordinal 90-day mRS. Conclusions In this post-hoc analysis, perfusion mismatch was not associated with functional outcomes and did not modify the effect of EVT in MeVO stroke. Conflict of interest UP: nothing to disclose. Figure 1 - belongs to Results