ABSTRACT NUMBER: ESOC2026A831 NIHSS-STRATIFIED EFFICACY OF REPERFUSION STRATEGIES IN ACUTE ISCHEMIC STROKE

Abstract Background and aims The optimal selection of reperfusion strategy in acute ischemic stroke (AIS) due to large vessel occlusion remains controversial, particularly across different levels of stroke severity. Stratification by baseline NIHSS score may help refine treatment selection. Aim To compare the efficacy and safety of intravenous thrombolysis (IVT), mechanical thrombectomy (MT), and bridging therapy (IVT+MT) across predefined NIHSS strata. Methods This retrospective observational study included 233 AIS patients treated in 2024. Groups were stratified by baseline NIHSS (<8, 8–10, 11–13, 14–16, 16–20, >20). Primary outcomes were neurological improvement (ΔNIHSS) and unfavorable functional outcome (mRS 3–6). Secondary outcomes were symptomatic intracranial hemorrhage (sICH) and in-hospital mortality. Results For NIHSS <8, no outcome differences were observed. In NIHSS 8–10, MT provided greater neurological improvement than IVT (p<0.05). In NIHSS 11–13, MT led to better functional outcomes than IVT (p<0.05), with bridging therapy offering no added benefit over MT alone. For NIHSS 14–16, bridging therapy was associated with superior neurological improvement versus MT (p<0.05). In NIHSS >16, outcomes remained modest regardless of approach. Safety analysis indicated higher sICH rates with invasive strategies in low NIHSS, but acceptable profiles in moderate-to-severe strokes. Conclusions The efficacy and safety of reperfusion therapies in acute ischemic stroke are strongly influenced by baseline stroke severity. An NIHSS-guided approach may support more tailored treatment decisions, favoring IVT in mild strokes, early consideration of MT in moderate strokes, selective use of bridging therapy in intermediate severity, and mandatory endovascular treatment in severe presentations. Conflict of interest This study was funded by the National Agency for Research and Development (NARD) of the Republic of Moldova, research project no. 25.80012.8007.09TC.