Endovascular Treatment for Acute Ischemic Stroke Due to Medium Vessel Occlusion: A Systematic Review with Meta-Analysis

Background/Objective: The benefit of endovascular treatment (EVT) in acute ischemic strokes (AIS) due to medium vessel occlusion (MeVO) remains unclear, as recent randomized controlled trials (RCTs) have shown neutral results. This meta-analysis examines the pooled efficacy and safety of EVT in MeVO. Methods: A systematic review and meta-analysis of two RCTs (DISTAL and ESCAPE-MeVO) involving 1073 participants was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The primary outcome was the risk ratios (RR) of excellent functional outcome, defined as modified Rankin score (mRS) 0–1 at 90 days. Secondary outcomes included mRS 0–2 and symptomatic intracranial hemorrhage (sICH). Results: The RR implied no significant difference between the two treatment arms; for the primary efficacy outcome, RR (mRS 0–1) was 0.95 (95% CI: 0.81–1.10; I 2 = 0%), and for the secondary efficacy outcome, RR (mRS 0–2) was 0.98 (95% CI: 0.88–0.09; I 2 = 10%). The EVT + best medical treatment (BMT) arm demonstrated a higher risk of sICH (RR: 2.39, 95% CI: 1.26–4.53; I 2 = 0%) and serious adverse events (SAE) (RR: 1.32, 95% CI: 1.11–1.56; I 2 = 0%), while mortality at 90 days (RR: 1.29, 95% CI: 0.94–1.76; I 2 = 16%) showed no significant difference. Conclusions: Our study showed that, in patients with AIS due to MeVO, EVT did not lead to better outcomes at 90 days when compared to BMT and was associated with a higher risk of sICH and SAEs compared to usual care, and this result was confirmed in a trial sequential analysis. PROSPERO registration: The study protocol was registered with the International Prospective Register of Systematic Reviews under the registration identification number CRD420250653970.