Endovascular treatment after stroke beyond 24 h vs 6-24 h: a propensity score-matched cohort study.
BACKGROUND: Endovascular thrombectomy (EVT) is the standard treatment for acute ischemic stroke due to anterior circulation large vessel occlusion (LVO) within 6-24 h. However, the safety and feasibility of EVT for anterior circulation strokes beyond 24 h remain uncertain. METHODS: We conducted a retrospective cohort study of consecutive patients with anterior circulation LVO who underwent EVT at Changhai Hospital from 2018 to 2023. Patients were stratified into late (6-24 h) and very late (>24 h) windows. Propensity score matching (PSM) was performed to adjust for baseline imbalances, including age, sex, NIHSS, ASPECTS, occlusion location, perfusion parameters, and vascular risk factors. The primary outcome was functional independence (modified Rankin Scale [mRS] ≤ 2) at 3 months. Secondary outcomes included successful reperfusion (TICI 2b-3) and symptomatic intracranial hemorrhage (sICH). RESULTS: Among 1043 screened patients, 429 patients with anterior circulation LVO were included after exclusions, comprising 373 in the late window and 56 in the very late window. PSM yielded 42 matched pairs. Compared with the late window group, the very late window group showed no statistically significant differences in functional independence (54.8% vs. 57.1%; OR = 0.908, 95% CI 0.382-2.153, p = 0.830), successful reperfusion (88.1% vs. 92.9%; OR = 1.800, 95% CI 0.481-7.096, p = 0.460), sICH (2.4% vs. 9.5%; OR = 0.232, 95% CI 0.012-1.652, p = 0.200), intraprocedural complications (26.2% vs. 19.0%; OR = 1.508, 95% CI 0.540-4.362, p = 0.440), or postoperative complications (33.3% vs. 35.7%; OR = 0.900, 95% CI 0.363-2.219, p = 0.820). CONCLUSIONS: In this selected, single-center cohort of anterior circulation LVO patients undergoing EVT, treatment initiated beyond 24 h appeared to have comparable effectiveness and safety to treatment initiated within 6-24 h. Definitive evidence requires confirmation from adequately powered randomized controlled trials.