Clinical and safety outcomes following endovascular treatment for large ischemic core stroke with Alberta Stroke Program Early Computed Tomography Score 3-5 in the 12-to 24-h time window.

Abstract

Introduction: Although the efficacy and safety of endovascular treatment (EVT) for large-core ischemic stroke have been proven, most trials used perfusion imaging or included early-window patients, limiting generalizability to the late window, particularly in developing countries.

Aim: We aimed to evaluate the safety and functional outcomes of EVT in large-core stroke patients treated between 12 and 24 h (late window) from last known well (LKW).

Methods: We conducted a prospective, multicenter observational study across four comprehensive stroke centers in Vietnam, enrolling consecutive patients who underwent EVT within 24 h of symptom onset between August 2023 and September 2024. Large core was defined by an Alberta Stroke Program Early CT Score (ASPECTS) of 3 to 5 on non-contrast computerized tomography (NCCT) or diffusion-weighted magnetic resonance imaging (DWI-MRI). Patients who underwent EVT within 12-24 h after LKW were compared to those treated before 12 h (early window). Primary and safety outcomes were independent ambulation (90-day modified Rankin scale (mRS) = 0-3) and symptomatic intracranial hemorrhage (sICH). Secondary outcomes were 90-day mRS 0-2, ordinal mRS, successful reperfusion (modified Thrombolysis in Cerebral Infarction score ⩾2b, early neurological deterioration (END)), and 90-day mortality.

Results: Of 1872 patients receiving EVT, 343 with large ischemic cores (median age = 64.0 years, 33.8% female) were included, with 103 (30.0%) treated in the 12- to 24-h window. Compared to early-window patients, late-window patients had lower rates of intravenous thrombolysis (2.9% vs. 32.9%, p < 0.001), higher brain MRI use (51.5% vs. 16.2%, p < 0.001), and longer pre-treatment imaging-to-groin puncture times (106 vs. 77 min, p < 0.001). After adjusting for confounders, there were no significant differences in 90-day mRS 0-3 (56.3% vs. 55.0%, adjusted odds ratio (aOR) = 0.71, 95% confidence interval (CI) = 0.39-1.28, p = 0.26), ordinal mRS (aOR = 1.21, 95% CI = 0.78-1.90, p = 0.39), and sICH (aOR = 1.12, 95% CI = 0.32-3.50, p = 0.85). Other secondary outcomes were also similar.

Conclusion: In patients with anterior circulation large vessel occlusion stroke and low ASPECTS, EVT at 12-24 h versus <12 h from symptom onset showed no significant differences in clinical or safety outcomes. Larger trials are needed to confirm these findings, especially in developing regions.