An umbrella review of systematic reviews and meta-analyses evaluating the efficacy and safety of mechanical thrombectomy for acute ischemic stroke

Mechanical thrombectomy (MT) is an established treatment for acute ischemic stroke (AIS) due to large vessel occlusion. However, evidence from multiple systematic reviews and meta-analyses varies across patient populations and clinical subgroups. This umbrella review aimed to synthesize and critically appraise the existing evidence on the efficacy and safety of MT in AIS. An umbrella review was conducted in accordance with PRISMA 2020 guidelines. PubMed/MEDLINE, Embase, Web of Science, and the Cochrane Database of Systematic Reviews were searched from inception to December 2025. Eligible reviews evaluated MT, with or without intravenous thrombolysis (IVT), in adults with AIS and reported outcomes including functional independence, mortality, recanalization, or hemorrhagic complications. Methodological quality was assessed using the AMSTAR-2 tool. Ten systematic reviews and meta-analyses published between 2015 and 2025 were included and were rated as high-to-moderate methodological quality. MT was consistently associated with improved functional independence and higher recanalization rates compared with standard medical therapy or IVT alone. Mortality outcomes were heterogeneous, with some reviews demonstrating reduced mortality and others showing no significant difference. Safety analyses generally showed no significant increase in symptomatic intracranial hemorrhage, although increased hemorrhagic risk was reported in certain populations, including anticoagulated and thrombocytopenic patients. Overall, current evidence from high- to moderate-quality systematic reviews supports the efficacy of MT in improving functional outcomes and recanalization in AIS. However, this umbrella review identifies persistent uncertainty across key clinical subgroups and highlights inconsistencies in mortality and safety outcomes.