Thrombectomy for distal medium vessel occlusion: a comprehensive meta-analysis of randomized controlled trials

Distal medium vessel occlusion (DMVO) accounts for a substantial proportion of acute ischemic strokes, yet the role of endovascular therapy (EVT) in this population remains uncertain.

PubMed, Scopus, Web of Science, and the Cochrane Library were systematically searched from inception through May 2026. Randomized and comparative studies evaluating EVT versus non-EVT strategies in acute ischemic stroke due to DMVO were included. Primary outcomes were excellent functional outcome (90-day modified Rankin Scale [mRS] 0-1), functional independence (mRS 0-2), symptomatic intracranial hemorrhage (sICH), and 90-day mortality. Pooled risk ratios (RRs) and risk differences were calculated using random-effects models.

Six randomized controlled trials involving 2,061 patients were included. EVT did not significantly improve excellent functional outcome (mRS 0-1) (RR, 1.19; 95% CI, 0.89-1.59), functional independence (RR, 1.07; 95% CI, 0.89-1.30), independent ambulation (RR, 0.97; 95% CI, 0.86-1.09), overall survival (RR, 0.97; 95% CI, 0.91-1.04), or reduce death or severe dependency (RR, 1.07; 95% CI, 0.76-1.50). Ninety-day mortality was also similar between groups (RR, 1.12; 95% CI, 0.73-1.71). Although sICH occurred more frequently with EVT, the difference did not reach statistical significance (RR, 2.31; 95% CI, 0.98-5.46; p = .054); however, this estimate was sensitive to the exclusion of a single study.

EVT was not associated with improved functional or survival outcomes in unselected patients with DMVO. Although sICH appeared more frequently with EVT, the difference was not statistically significant. Current evidence does not support routine EVT in unselected DMVO.