Abstract WMP89: Reperfusion Pattern as a Predictor of Final Infarct Growth in Patients With Anterior Large Vessel Occlusion Ischemic Stroke

Abstract

Aim: The first pass effect (FPE) and complete sudden recanalization (cSR) have been identified as an indicator of favorable clinical outcome. We aimed to compare final infarct volume (FIV) according to different reperfusion pattern. Methods: We included consecutive patients admitted with an anterior LVO stroke (intracranial internal carotid artery, MCA-M1) who underwent endovascular treatment between January 2018 and April 2022. Patients with partial or no-reperfusion (eTICI 0-2b) were excluded. Final complete reperfusion (TICI 2c-3) was categorized as achieved at first pass (FPE) or in subsequent passes as sudden (cSR: from TICI 0-1 to TICI 2c-3 in a single pass) or progressive (PR: interim partial recanalization). FIV was quantified using an automatic segmentation tool (Methinks AI) on 24-hour NCCT. Aggregated infarct distribution heatmaps were generated to compare FIV distribution. Results: Of 316 consecutive patients, complete reperfusion was achieved in 202 patients (63.9%). Reperfusion patterns were as follows: FPE (109/202, 54.0%), cSR (28/202, 13.9%) and PR (65/202, 32.1%). The mean FIV was 28.1mL (95%CI 19.1-37.1), 49.5mL (95%CI 18.8-80.2) and 58.4mL (95% CI 37.6-79.2) in FPE patients, cSR and PR patients, respectively (p=0.014). After adjusting for confounders, FPE and cSR patterns were independently associated with a reduced FIV (FPE: -61.7%, 95%CI -77.2% to -35.8%, p<0.001; cSR: -39.7%, 95%CI -63.8% to 0.6%, p=0.05). The rate of excellent clinical outcome (mRS 90d 0-1) was higher in FPE (36.1%) and cSR (35.7%) groups compared to the PR group (20.3%, p=0.081). Conclusion: Improved clinical outcomes in patients with FPE and cSR patterns seem to be influenced by reduced infarct volume in a stepwise manner (FIV FPE<cSR<PR). PR may reflect clot fragmentation and embolization, contributing to infarct growth and worse outcomes. Reperfusion patterns should be explored for selecting target populations for adjunctive neuroprotective therapies during EVT.