ABSTRACT NUMBER: ESOC2026A1759 PREDICTIVE VALUE OF 12-LEAD ECG PARAMETERS FOR DETECTING ATRIAL FIBRILLATION AFTER STROKE OR TRANSIENT ISCHEMIC ATTACK OVER 24 MONTHS

Abstract Background and aims Standardised post-stroke pathways for atrial fibrillation (AF) detection are lacking. The clinical AS5F-score estimates the probability of detecting AF during 72h-Holter monitoring after ischemic stroke or transient ischemic attack (TIA). We tested whether baseline 12-lead ECG parameters add predictive value beyond AS5F. Methods MonDAFIS was an investigator-initiated, multicentre study randomising patients with ischemic stroke/TIA without known AF to prolonged in-hospital Holter monitoring (N=3,465). In this post-hoc analysis, manual caliper measurements from admission 12-lead ECG were available in the intervention group. ECG-parameters included Bazett-corrected QT-interval(QTc), P-wave area, P-wave duration(>120ms), PR-interval(>200ms), QRS-complex duration(>120ms), P-wave terminal-force(V1), premature atrial&ventricular contractions, and abnormal P-wave-axis(<0°or >75°). Candidate variables were added to AS5F in a LASSO-guided multivariable logistic regression to predict AF in-hospital and within 24 months. Results Of 1,714 intervention-group patients, 1,659 were included. AF was detected in-hospital in 92 and within 24 months in 192 patients. AS5F was associated with in-hospital AF (OR per 1-point increase 1.06, 95%CI 1.04-1.09, p<0.001) and 24-month AF (OR 1.05, 95%CI 1.03-1.07, p<0.001). No ECG-parameter improved prediction of in-hospital AF beyond AS5F. For 24-month AF, prolonged QRS (OR 3.29, 95%CI 1.59-6.78, p=0.001) and prolonged P-wave duration (OR 1.87, 95%CI 1.01-3.47, p=0.045) were statistically significantly associated. Adding LASSO-selected ECG parameters improved discrimination (area-under-the-curve 0.681 vs. 0.651, p=0.021). Conclusions Prolonged QRS and P-wave duration were associated with AF-detection within 24 months, supporting their potential value for selecting patients for prolonged ECG monitoring after stroke/TIA. Conflict of interest This work was supported by an unrestricted research grant from Bayer Vital GmbH, Germany. MCO, MB, ST, FS and CK do not have potential conflicts of interests outside the submitted work. ME reports grants from Bayer and fees paid to the Charité from Amgen, AstraZeneca, Bayer, Boehringer Ingelheim, Bristol-Myers-Squibb, Covidien, Daiichi Sankyo, Glaxo Smith Kline, Novartis, Pfizer and Sanofi,all outside the submitted work. KGH reports speaker's honoraria, consulting fees, lecture honoraria and/or study grants from Abbott, Amarin; AstraZeneca, Bayer Healthcare, Biotronik, Boehringer Ingelheim, Boston Scientific, Bristol-Myers Squibb, Daiichi Sankyo, Edwards Lifesciences, Medronic, Novartis, Pfizer, Portola, Premier Research, Sanofi, SUN Pharma, and W.L. Gore and Associates. RBS has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme under the grant agreement No. 648131, from the European Union’s Horizon 2020 research and innovation programme under the grant agreement No. 847770 (AFFECT-EU), from the European Union’s Horizon Europe research and innovation programme under the grant agreement ID: 101095480 and German Center for Cardiovascular Research (DZHK e.V.) (81Z1710103 and 81Z0710114); German Ministry of Research and Education (BMBF 01ZX1408A) and ERACoSysMed3 (031L0239). Wolfgang Seefried project funding German Heart Foundation. RBS has received lecture fees and advisory board fees from BMS/Pfizer and Bayer outside this work.