P4780Effectiveness and safety of non-vitamin k antagonist oral anticoagulants in patients with atrial fibrillation and valvular heart disease

Abstract Background Patients with atrial fibrillation (AF) often have concomitant valvular heart disease (VHD), especially in Asia. There are limited data on non-vitamin K antagonist oral anticoagulants (NOAC) impact on outcomes for stroke prevention and bleeding for these patients in real world clinical practice. Purpose To investigate the effectiveness and safety of NOACs compared with warfarin in patients with AF and associated Evaluated Heartvalves, Rheumatic or Artificial (EHRA) type 2 VHD. Methods We identified oral anticoagulants naive patients with AF and EHRA type 2 VHD from the Korean National Health Insurance Service database between 2014 and 2016 (n=2,671 taking warfarin; n=3,058 taking NOAC). Six clinical outcomes including ischemic stroke, intracranial hemorrhage (ICH), gastrointestinal bleeding (GI), major bleeding, all-cause death, and their composite outcome and fatal clinical events (any events that led to death within 30-day of its occurrence) were evaluated. Inverse probability of treatment weighting (IPTW) method was used to balance covariates between the two groups. Results After weighted using 5% trimmed IPTW method (n=2371 taking warfarin; n=2792 taking NOAC), the mean age was 71.2 years, male was 57% and CHA2DS2-VASc score was 3.9. During a mean 1.4-year follow-up, weighted incidence rate of ischemic stroke, ICH, GI bleeding, and all-cause death were lower in the NOAC group than in the warfarin group. Compared to warfarin, NOACs were associated with lower risks of ischemic stroke (hazard ratio [HR] 0.71, 95% confidence interval [CI] 0.53–0.96), GI bleeding (HR 0.50, 95% CI 0.35–0.72) and major bleeding (HR 0.61, 95% CI 0.45–0.80). Although NOAC and warfarin groups showed similar incidence rate of ICH, NOAC group was associated with a significantly lower risk of fatal ICH compared to warfarin group (HR 0.28, 95% CI 0.07–0.83). Overall, NOACs were associated with a lower risk of the composite outcome (HR 0.68, 95% CI 0.58–0.80). For an exploratory analysis, patients with EHRA type 1 VHD (n=366 taking warfarin; n=345 taking NOAC) was evaluated. In multivariable Cox regression analysis, NOAC group showed a comparable risk of ischemic stroke, ICH, all-cause death and composite outcome. Clinical outcome in AF patients with VHD Conclusion In this nationwide Asian AF population with EHRA type 2 VHD, NOAC use was associated with lower risks of ischemic stroke, major bleeding, all-cause death, and the composite outcome compared to warfarin.