Predictors of functional outcome after endovascular thrombectomy in patients with large ischemic core based on DWI-ASPECTS

Abstract Background Several clinical trials have shown the benefit of endovascular thrombectomy (EVT) in patients with large ischemic core infarction. However, the imaging selection modalities used for patient selection have differed across studies. This study aimed to assess the efficacy, safety, and prognostic factors of EVT in patients with large ischemic core selected only on the basis of Diffusion-Weighted Imaging Alberta Stroke Program Early CT Score (DWI-ASPECTS). Method This single-center study, conducted from 2019 to 2024, included patients with anterior circulation acute large vessel occlusion and stratified them into three groups according to DWI-ASPECTS: non-large ischemic core (≥ 6) treated with EVT ( n = 77), large ischemic core (3–5) treated with EVT ( n = 91), and large ischemic core (3–5) treated with medical management alone ( n = 70). The primary outcome was functional independence at 90 days, defined as a modified Rankin Scale (mRS) score of 0–2. Secondary endpoints included symptomatic intracranial hemorrhage (sICH) within 48 h and mortality within 90 days. Multivariate binary logistic regression was performed to identify factors associated with functional independence in the large-ischemic-core EVT group. Results Patients with large ischemic core treated with EVT had a significantly higher rate of 90-day functional independence than those who received medical management (53.8% vs 28.6%, P = 0.001). No significant differences in sICH or mortality were observed between the large-ischemic-core EVT and medical management groups. However, compared with patients with non-large ischemic core treated with EVT, those with large ischemic core treated with EVT had a lower rate of functional independence (53.8% vs 70.1%, P = 0.039). In the large ischemic core EVT group, intravenous thrombolysis (OR 0.164, P = 0.018) and parenchymal hematoma type 2 (PH2) hemorrhage (OR 25.641, P = 0.012) were independent predictors of 90-day outcomes. Conclusion In this cohort, EVT was associated with improved 90-day functional outcomes in patients with large ischemic core (DWI-ASPECTS 3–5) compared with medical management alone, without a statistically significant increase in sICH or mortality. Intravenous thrombolysis and PH2 hemorrhage were identified as independent predictors of outcome. These results require further confirmation in larger and adequately powered studies.