Safety and Effectiveness Analysis of Endovascular Treatment versus Standard Medication Treatment in Patients with Progressive Acute Ischemic Stroke with Large Vessel Occlusion Stroke in the Ultra-Late Time Window: A Propensity Score Matched Cohort Study.

Background: The time from onset to symptom deterioration in ischemic stroke often exceeds 24 hours, and this ultra-late time window is excluded from the endovascular treatment (EVT) guideline. This study aimed to explore the safety and efficacy of EVT in progressive acute ischemic stroke with large vessel occlusion stroke patients with onset to symptom deterioration times of 24 hours-7 days.

Methods: Progressive stroke patients with time window of 24 hours-7 days treated at our hospital over the past 6 years were retrospectively collected. Patients were categorized into EVT and standard medication treatment (SMT) groups based on the treatment approach. Patients were matched using propensity score matching. Safety outcomes primarily included 3-month mortality and symptomatic intracranial hemorrhage; efficacy outcome primarily included functional independence (3-month modified Rankin scale ≤ 2).

Results: A total of 396 patients were included in the study, with 86 (21.7%) in EVT and 310 (78.3%) in SMT group. There were 140 remaining after propensity score matching, with 70 in each group (50%). Compared to SMT group, EVT group had higher functional independence (52.9% vs. 15.7%, odds ratio [OR] = 7.504, 95% confidence interval [CI] 2.141-14.093, P < 0.001) and lower 3-month mortality (14.3% vs. 40.0%, OR = 0.412, 95% CI 0.099-0.856, P < 0.001). EVT was also associated with higher symptomatic intracranial hemorrhage (25.7% vs. 5.7%, OR = 9.926, 95% CI 1.874-36.547, P < 0.001).

Conclusions: For patients with progressive acute ischemic stroke with large vessel occlusion in the ultra-late time window, EVT remains a viable treatment approach.