ABSTRACT NUMBER: ESOC2026A2343 HYPOPERFUSION INTENSITY RATIO AND CBV INDEX AS IMAGING BIOMARKERS OF PROGNOSIS AND TREATMENT RESPONSE IN LARGE-CORE STROKE: A POST-HOC ANALYSIS OF THE LASTE RANDOMIZED TRIAL

Abstract Background and aims Randomized controlled trials demonstrated the benefit of mechanical thrombectomy (MT) over best medical treatment (BMT) in acute ischemic stroke due to large-vessel occlusion with a large core. Baseline perfusion heterogeneity may modulate this effect. We assessed the prognostic value of the hypoperfusion intensity ratio (HIR) and the cerebral blood volume (CBV) index, reflecting collateral status. Methods We performed a post-hoc analysis of the LASTE trial, including patients with baseline perfusion imaging, processed by RAPID®. In main analysis, HIR and CBV index were dichotomized by the median and treated as continuous variables in secondary analyses. The main outcome was independent ambulation (modified Rankin Scale [mRS] 0–3) at 90 days. Treatment effects are presented as risk ratios (RR). Results 132 patients were included (median HIR= 0.67; median CBV index= 0.57). Higher HIR identified patients with worse prognosis, without evidence of heterogeneity in the benefit of MT. In the low-HIR subgroup, independent ambulation occurred in 47.4% MT patients versus 17.9% BMT patients (RR 2.65, 95%CI=1.12–6.28). In the high-HIR subgroup, the corresponding rates were 16.7% and 6.7%, respectively (RR 2.50, 95%CI=0.54–11.49). Similar results were found with the CBV index. In the low-CBV index subgroup, independent ambulation occurred in 21.6% of MT patients versus 7.1% of BMT patients (RR 3.03, 95%CI=0.70–13.16). In the high-CBV index subgroup, the corresponding rates were 44.4% and 16.7%, respectively (RR 2.67, 95%CI=1.11–6.43). Conclusions In large core patients, HIR and CBV index stratify prognosis, but do not seem to modulate the effect of MT. Conflict of interest Adrien ter Schiphorst has nothing to disclose. Caroline Arquizan received presentation fees from Amgen and Medtronic. Laurine Cadart has nothing to disclose. Julien Labreuche has nothing to disclose. Nicole Yuen has nothing to disclose. Bertrand Lapergue received grants from Balt, MicroVention, Phenox. Tudor G. Jovin is advisor and investor for Anaconda, Baskin Biosciences, Route92, Viz.ai, Galaxy Therapeutics, Gravity, StataDx, FreeOx, Kandu, and Methinks; received personal fees in his role on Cerenovus DSMB and steering committee and on Contego Medical screening committee; and received grant support from Medtronic and Stryker Neurovascular. Gregory W. Albers reports stock holdings in iSchemaView and compensation from Biogen, iSchemaView, and Genentech for consultant services. Vincent Costalat received consultation fees from Johnson & Johnson and Penumbra, educational grant, consultation fees, research grant from Medtronic, Stryker, MicroVention, Cerenovus, and Balt; educational grant and consultation fees from Phenox.