Endovascular Thrombectomy in Patients With Largest Baseline Infarcts (ASPECTS 0–2): An Ancillary Analysis of the LASTE Trial

BACKGROUND: Endovascular thrombectomy (EVT) has demonstrated benefits in patients with ischemic stroke and large-vessel occlusions, but its efficacy and safety in patients with the largest baseline infarcts (Alberta Stroke Program Early Computed Tomography Score [ASPECTS] 0-2), remain controversial. This study aimed to evaluate the efficacy and safety of EVT in early presenting patients with ASPECTS 0 to 2 compared with medical care alone. METHODS: This post hoc analysis of the multicenter, randomized LASTE trial ([Large Stroke Therapy Evaluation]; patients ≤80 years, ASPECTS 0-5, proximal anterior circulation large-vessel occlusion, randomization within 6.5 hours of last known well) evaluated the subgroup with ASPECTS 0 to 2, representing those with large baseline infarcts without an upper size limit, randomized to receive EVT plus medical care or medical care alone. Primary outcomes included the distribution of the modified Rankin Scale score at 90 days. Secondary outcomes included mortality, infarct volume growth at 24 hours, the incidence of symptomatic intracranial hemorrhage and modified Rankin Scale score at 180 days. The LASTE trial was conducted and reported in accordance with the CONSORT guidelines (Consolidated Standards of Reporting Trials). RESULTS: Median age was 72 years and 55.8% were women. Among the 181 patients with ASPECTS 0 to 2 (median core volume 156 mL [25th-75th percentiles, 121-204 mL]), at 90 days after randomization, EVT improved functional outcomes (generalized odds ratio, 1.81 [95% CI, 1.32-2.47]) and reduced mortality (38.4% versus 59.6%; relative risk, 0.64 [95% CI, 0.47-0.89]), which translated predominantly into an increase in the proportion of modified Rankin Scale score of 0 to 3 in the EVT group (31.4% versus 8.5%; relative risk, 3.69 [95% CI, 1.77-7.68]). A significant reduction in infarct growth volume was observed in the EVT group compared with medical care (mean difference, -70.3 mL [95% CI, -94.2 to -46.3]). Rates of symptomatic intracranial hemorrhage were 12.9% versus 4.5%, respectively (relative risk, 2.85 [95% CI, 0.94-8.60]). CONCLUSIONS: EVT improves functional outcomes and reduces mortality in patients with ASPECTS 0 to 2. These findings support the concept that in patients aged <80 years presenting within early time window (6.5 hours) with unlimitedly large infarct (predominantly selected using magnetic resonance imaging), the infarct size in isolation should not be used to disqualify patients from endovascular treatment. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03811769.