ABSTRACT NUMBER: ESOC2026A1464 PREDICTORS OF OUTCOME IN M2 MIDDLE CEREBRAL ARTERY ENDOVASCULAR THROMBECTOMY

Abstract Background and aims Endovascular thrombectomy (EVT) is the established treatment for acute ischemic stroke (AIS) caused by large vessel occlusion. Medium vessel occlusions (MeVOs) account for 25-40% of all AIS. While EVT for MeVO is increasingly performed, robust clinical evidence for its efficacy remains limited. Methods We evaluated consecutives patients with AIS due to M2 medium cerebral artery (MCA) occlusion, treated with EVT alone or in combination with intravenous thrombolysis. Demographic variables, clinical outcomes (NIHSS, 3-month mRS) and radiological outcomes (successful recanalization, symptomatic intracerebral hemorrhage [sICH]) were recorded. Results 154 patients with M2 MCA occlusion were recruited, with 28,4% treated in the extended time window based on CT perfusion criteria. Median age was 74.22 years, median NIHSS score was 12.57. Primary EVT was performed in 83 patients (53.9%), while 71 (46.1 %) received combined therapy. Successful recanalization (TICI 2b-3) was achieved in 90.9%. Favorable 90-day outcome (mRS 0-2) was observed in 51.3%, while sICH occurred in 4.88%. Younger age (p=0.02) and successful recanalization (p=0.01) were identified as independent predictors of favorable outcomes. In the extended time window group, the CT perfusion ischemic core volume significantly predicted 3-month mRS (p=0.04). No significant outcome differences was found between primary EVT and combined therapy, but subgroup analysis showed a higher likelihood of favorable outcome with combined therapy (p=0.04) in patients younger than 80 years. Conclusions This study supports the efficacy of mechanical thrombectomy for MeVO. Further research is warranted to refine optimal treatment strategy for MeVO in clinical practice. Conflict of interest Marco Erta: nothing to disclose