Efficacy And Safety Of Endovascular Treatment Vs Medical Treatment In Anterior Circulation Stroke Beyond 6 Hours: A Systematic Review And Meta-Analysis

Background & Objective: Endovascular treatment is the widely accepted treatment for patients with anterior circulation stroke within 6 hours of onset of stroke. We aimed to evaluate the advantages of endovascular treatment compared to standard medical treatment in treating patients with anterior circulation stroke beyond the 6-hour therapeutic window. Methods: We reviewed the literature concerning endovascular treatment versus medical treatment beyond the 6-hour therapeutic window. Using random-effects meta-analysis, we evaluated the following outcomes: modified Rankin scale in the three-month follow-up [excellent outcome (mRS=1), functional independence (mRS=2), moderate outcome(mRS=3)], recanalization rate at 24 hours, mortality at 90 days or in-hospital, symptomatic intracranial hemorrhage, parenchymal hematoma type 2 and hemorrhagic infarction 1. Results: Four studies including 642 patients were evaluated. Endovascular treatment was associated with higher odds of excellent outcome (OR 2.55; 95% CI 1.48 to 4.41,), functional independence (OR 3.64; 95% CI 2.43 to 5.45), moderate outcome (OR 2.70; 95% CI 1.95-3.74) and recanalization rate at 24 hours (OR 8.81; 95%CI 2.81 to 27.69) compared to MT. No difference in the rates of mortality, symptomatic intracranial hemorrhage, parenchymal hematoma type 2 or hemorrhagic infarction 1 was found between the 2 groups. Studies using strict perfusion imaging inclusion selection showed better moderate outcome in comparison to the studies without perfusion imaging inclusion selection (P<0.012).Conclusion: Our study highlights the superiority of endovascular treatment over standard medical treatment alone for treating patients with anterior circulation stroke beyond 6 hours since stroke onset, although more studies are required for further investigation. Standard of strict selection for eligible patients before endovascular treatment should be based on DAWN or DEFFUSE 3 inclusion criteria.