Abstract Number: Esoc2026a1728 Evt in Patients With Tandem Lesions: Effect of Cas and Evt Devices

Abstract Background and aims 15–20% of patients with acute ischemic stroke (AIS) due to anterior large vessel occlusion present with ipsilateral extracranial carotid artery stenosis 50% or occlusion, termed tandem lesions (TLs). The optimal endovascular treatment (EVT) strategy for TLs remains uncertain, particularly regarding carotid artery stenting (CAS) and thrombectomy technique. This study compared outcomes in TL patients treated with or without CAS during EVT and the impact of different thrombectomy approaches (aspiration alone AA, stent retriever alone SRA, or combined approach CA). Methods EVA-TRISP is a large international multicenter cohort study including consecutive AIS patients treated with EVT, 2016-2023. Outcomes included 3-month modified Rankin Scale (mRS), good functional outcome (mRS 0–2), complete angiographic recanalization, symptomatic intracranial hemorrhage (sICH), and all-cause mortality. Results Among 13,702 EVT-treated patients, 1,545 (11.3%) had TLs; 596/1,545 (39%) underwent CAS. CAS was associated with higher odds of better functional outcome (adjusted odds ratio aOR 1.33, 95% CI 1.09–1.62) without increased sICH or mortality. AA was used in 28.1%, SRA in 26.8%, and CA in 45.1%. SRA and CA were associated with higher odds of complete recanalization (aOR 1.96 95% CI 1.38–2.78 & 1.99 95% CI 1.48–2.67), compared to AA. CA was not associated with functional benefit but rather with sICH (aOR 2.50, 95% CI 1.28–4.89). Conclusions CAS during EVT was associated with improved functional outcomes in TL patients without increased hemorrhagic risk or mortality. Stent retriever use improved recanalization, while combined techniques increased sICH risk without added clinical benefit. Conflict of interest T. van Elk: Nothing to disclose. N. Wali: Nothing to disclose. M. Uyttenboogaart: Nothing to disclose. H. Gensicke: Nothing to disclose. S. Engelter: Nothing to disclose. P.J. Nederkoorn: Nothing to disclose.