ABSTRACT NUMBER: ESOC2026A2033 THROMBOLYSIS AND OUTCOMES IN ISCHEMIC STROKE IN PATIENTS RECEIVING ORAL ANTICOAGULATION: A POOLED INDIVIDUAL PATIENT DATA ANALYSIS FROM TWO NATIONAL STROKE REGISTRIES

Abstract Background and aims Prior oral anticoagulant (OAC) therapy in patients with atrial fibrillation (AF) and acute ischemic stroke (AIS) may influence eligibility for intravenous thrombolysis (IVT) and clinical outcomes compared with patients without prior OAC. Methods We pooled individual patient data from two national stroke registries (Switzerland, Norway). We assessed the association of prior vitamin K antagonist (VKA) or direct oral anticoagulant (DOAC) therapy versus no prior OAC with favourable functional outcome at 3 months (mRS 0-2), 3-month mortality and symptomatic intracranial haemorrhage (sICH). Among IVT-eligible patients, we evaluated the association of IVT with outcomes stratified by prior OAC status. Results 19,188 patients with AF and AIS were included (mean age 80 (SD 9.6)), 19.9% on VKAs, 23.5% on DOACs and 56.6% with noOAC, IVT rates 10.2% VKA, 6.3% DOAC, 27.5% noOAC. Compared with noOAC, neither prior VKA (adjusted odds ratio (aOR) 1.01, 95% CI 0.87-1.18) nor prior DOAC therapy (aOR 1.11, 95% CI 0.96-1.28) were associated with higher odds of favorable functional outcome. DOAC therapy was associated with lower odds of mortality (aOR 0.84, 95% CI 0.71-0.98), while VKA therapy showed a numerical trend toward lower odds of mortality (aOR 0.86, 95% CI 0.72–1.01). Among IVT-eligible patients, the association of IVT with outcome and mortality did not differ by prior OAC status. Rates of sICH were similar across groups. Conclusions In AIS patients with AF, preceding DOAC therapy was associated with lower mortality but not improved functional outcome. IVT was associated with favourable outcomes without heterogeneity across OAC types or safety concerns. Conflict of interest Elisabeth Forfang: nothing to disclose. Bernhard M Siepen: Reports research support from the Swiss Heart Foundation, the Swiss Academy of Medical Sciences and Bangerter-Rhyner-Foundation, and Inselspital Bern, Department of Teaching and Research, unrelated to the current project. Thomas R Meinel: is the global PI of the DO-IT RCT and registry. He reports research support of the Swiss National Science Foundation; research support of the Swiss Heart Foundation, Bangerter Rhyner Foundation and the Horten Foundation; research grants from Boehringer Ingelheim; consultancies for Medtronic, and Boehringer Ingelheim (fees paid to institution). Participation in an advisory board for Boehringer Ingelheim (fees paid to institution). Member of a clinical event committee (CEC) of the SWISS-AF study. Stefan Engelter: reports support of the Swiss National Science Foundation and of the Swiss Heart Foundation (unreacted to the current project). Torgeir Bruun Wyller: has received lecture honorary from NovoNordisk. Espen Saxhaug Kristoffersen: nothing to disclose. David Julian Seiffge: nothing to disclose. Ole Morten Rønning: nothing to disclose.