Abstract WP249: Prolonged Venous Transit is Associated with Unfavorable Functional Outcomes in Large Core Stroke

Background: Large core acute ischemic stroke (AIS) caused by large vessel occlusion (LVO) is associated with high rates of disability despite mechanical thrombectomy (MT) treatment. Recent studies suggest that prolonged venous transit (PVT) may indicate impaired venous drainage, influencing functional outcomes. However, its prognostic value in large core AIS-LVO patients remains unclear. Methods: We conducted a retrospective cohort study using data from consecutive patients with AIS-LVO and large ischemic core volumes (ASPECTS <6 or relative cerebral blood flow < 30% volume ≥50 mL; per SELECT-2 trial definition) between September 1, 2016 and September 2, 2024. The primary outcome was unfavorable functional recovery at 83 90 days, defined as a modified Rankin Scale (mRS) score of 4-6. Results: 100 patients met inclusion criteria, and 41 (41%) had PVT. Unfavorable functional outcomes were more frequent in the PVT+ group (59% vs. 37%, p=0.036). Multivariable analysis confirmed that PVT was independently associated with unfavorable outcomes (adjusted OR 4.07, 95% CI 1.15-14.4, p=0.03), even after accounting for penumbra size (Tmax >6s) and large core volumes (rCBF <30%). Other predictors included older age (adjusted OR 1.07, 95% CI 1.02 to 1.11, P=0.003), higher admission NIHSS (adjusted OR 1.16, 95% 89 CI 1.05 to 1.29, P=0.005), and larger rCBF <30% volume (adjusted OR 1.02, 95% CI 1.00 to 1.04, P=0.032). Conclusions: PVT is independently associated with unfavorable outcomes in patients with large core AIS-LVO. These findings suggest PVT may serve as a prognostic marker, warranting further investigation in larger prospective studies to guide treatment decisions in this high-risk population.