ABSTRACT NUMBER: ESOC2026A1875 ASSOCIATION OF CORTICAL VENOUS OPACIFICATION PATTERNS AND OUTCOMES IN PATIENTS WITH TANDEM CAROTID OCCLUSION FROM THE ACT TRIAL

Abstract Background and aims Cortical venous opacification may reflect ischemic severity in large vessel occlusion (LVO) strokes, but its association with outcomes in tandem occlusion (cervical ICA occlusion with concurrent intracranial ICA, M1, or M2 occlusion) is unclear. Methods We performed a post-hoc analysis of the alteplase compared to tenecteplase (AcT) trial. The sphenoparietal sinus, superficial middle cerebral vein, and vein of Labbé received a Cortical Venous Opacification Score (COVES) graded 0-2 on CTA (total 0–6: lower scores indicate poorer filling). COVES+ with the internal cerebral vein (total 0-8) was also assessed. Associations with functional and safety outcomes were evaluated using regression models adjusted for age, NIHSS, ASPECTS, and door-to-needle time. Results Among 127 patients with tandem occlusion (median age 69 [IQR 60–78] years; 32% female), 17 (13.4%) had a COVES of 0 and 110 (86.6%) had COVES >0. Compared to COVES >0, patients with COVES 0 had higher NIHSS (median 20 [IQR 18–22] vs 16 [IQR 10–20], p=0.002), lower ASPECTS (median 8 [range 4–10] vs 8 [range 5–10], p=0.031), and a higher proportion with poor collaterals (29.4% vs 8.2%). COVES score was not associated with 90-day functional outcomes (ordinal mRS: acOR 1.04 [95% CI 0.86-1.26]), mortality, or symptomatic intracranial hemorrhage. COVES+ also showed no associations with outcomes. Conclusions Cortical venous opacification was not associated with functional or safety outcomes in patients with tandem occlusion in the AcT trial. These findings may reflect the small sample size or differences from the broader LVO population, warranting further study. Conflict of interest CreeAnn Phillips: nothing to disclose, Nahal Farhani: nothing to disclose, Alexandre Poppe: nothing to disclose, Bijoy Menon:nothing to disclose, Nishita Singh: nothing to disclose, Fouzi Bala: nothing to disclose, Taha Aslan: nothing to disclose, Mohammed Almekhlafi: nothing to disclose, Katrina Ignacio: nothing to disclose.