Abstract 9831: Antithrombotic Regimens After Transcatheter Aortic Valve Replacement: Comparison of Medium-Term Outcomes

Abstract

Introduction: Bioprosthetic valve thrombosis is a recognized cause of bioprosthetic valve dysfunction. It was found to be associated with accelerated bioprosthetic degeneration and higher rates of valve re-replacement. Hypothesis: Warfarin for 3 months after transcatheter aortic valve replacement (TAVR) protects against accelerated valve degeneration and is therefore associated with better outcomes compared to dual antiplatelet (DAPT) and single antiplatelet therapies (SAPT). Methods: Adult patients who underwent TAVR (2012-2019) were identified retrospectively (n=1,501). Patients with atrial fibrillation were excluded (n=657). Patients were classified into warfarin, DAPT, and SAPT groups based on antithrombotic regimen. Structural valve degeneration (SVD) was considered when patients developed new ≥ moderate trans-prosthetic regurgitation, increase in mean gradients ≥10 mmHg from baseline, or when gradients exceeded 20 mmHg. Discharge date was considered time zero. Results: Overall, 844 patients [mean age 80 (±9), 43% females, mean Society of Thoracic Surgeons risk score 6.7 (±5.0)] were included. Warfarin was used in 633 (75%) patients, DAPT in 164 (19%), and SAPT in 47 (6%). Median follow-up time was 2.5 (IQR 1.2-3.9) years. There was no difference in outcomes of ischemic stroke, death, valve re-intervention, SVD, their composite endpoint, or hemorrhagic stroke and hemorrhagic stroke/RBC transfusion events (Figures 1 & 2), even after adjustment for confounders. Conclusion: Warfarin after TAVR was not associated with better clinical or hemodynamic outcomes or with worse adverse events compared to DAPT and SAPT.