Thrombectomy for Distal Medium Vessel Occlusion: A Meta-Analysis of Randomized Controlled Trials.

Background: Approximately 25% to 40% of all acute ischemic strokes result from distal medium vessel occlusions. However, the effectiveness and safety of thrombectomy for distal medium vessel occlusions remain uncertain.

Methods: A systematic search of PubMed, Cochrane, and Embase was conducted for randomized controlled trials published until February 2025. The primary outcomes were functional outcomes at 90 days (excellent, good, and favorable). The secondary outcomes included symptomatic intracranial hemorrhage (ICH), any ICH, and mortality at 90 days.

Results: Three studies involving 1246 patients with stroke with distal medium vessel occlusion were included (614 patients receiving thrombectomy; others with medical management). At 3 months, the odds ratio for an excellent functional outcome was 0.92 (95%, 0.72-1.17), for a good functional outcome was 0.87 (95% CI, 0.70-1.09), and for a favorable functional outcome was 0.84 (95% CI, 0.64-1.10), indicating no significant difference between the 2 groups. However, thrombectomy was associated with a higher risk of hemorrhage, with an odds ratio of 2.18 (95% CI, 1.24-3.83) for symptomatic ICH and 1.96 (95% CI, 1.54-2.50) for any ICH. Mortality at 3 months was similar between the groups, with an odds ratio of 1.20 (95% CI, 0.85-1.70).

Conclusions: Thrombectomy did not significantly improve functional outcomes or reduce mortality but increased symptomatic ICH and any ICH. Further recent randomized controlled trials are needed to define subgroups that may benefit.

Registration: PROSPERO CRD420251073344.