Ischemic core volume is associated with hemorrhagic transformation post endovascular thrombectomy

Symtomatic hemorrhagic transformation(sHT) was defined as any intracerebral hemorrhage that combined with clinical deterioration. While recent studies showed low rates of sHT in large core ischemic strokes treated with endovascular thrombectomy (EVT), the specific impact of core size on overall hemorrhagic transformation (HT) remains unclear. We aim to investigate the relationship between ischemic core size and development of HT post thrombectomy.

This prospective study enrolled acute ischemic stroke (AIS) patients with anterior large vessel occlusion undergoing EVT who had baseline MRI from 2017 to 2019. Pre-EVT Arterial Spin Labeling (ASL) and Diffusion-Weighted Imaging (DWI) scans were performed for volume calculations. Primary outcome was HT assessed within 72 h post EVT. Multivariable logistic regression was used to analyze the associations between baseline DWI and ASL volumes and HT occurrence. Discriminative ability for HT was compared using receiver operating curve analysis (c-statistic).

We included 101 patients (median age: 64 [IQR 56-74] years, baseline NIHSS 13 [IQR 9-16]). Median DWI and ASL volume were 21.0 ml [IQR 8.3-47.2] and 105 ml [59.5-172.9], respectively. 16.8 % recieved intravenous thrombolysis before EVT. HT occurred in 36.6 % of patients, including 16.8 % with sHT. Baseline DWI volume was independently associated with HT (OR = 1.030, 95 % CI 1.008 to 1.053, P = 0.009), while ASL volume wasn't statistically significant(P = 0.330). The DWI model was superior to ASL model in predicting HT within 72 h (c-statistic, 0.787).Neither DWI (P = 0.149) nor ASL volume (P = 0.834) effectively indicated sHT.

DWI-based ischemic core volume correlates significantly with HT within 72 h post successful thrombectomy. This highlights the potential clinical utility of DWI in guiding treatment decisions for this population.