An external validation of DOAC score in patients with atrial fibrillation following transcatheter aortic valve replacement

Abstract Background Bleeding events, particularly in patients with atrial fibrillation (AF) and those with severe aortic stenosis undergoing transcatheter aortic valve replacement (TAVR), are a major clinical concern and are associated with a worse prognosis. The DOAC Score (1) has recently been introduced to predict bleeding risk in patients with AF taking direct oral anticoagulants (DOACs). However, further validation is required to confirm its ability. Objective This study aims to evaluate the predictive ability of the DOAC Score for bleeding events in Asian patients with AF undergoing TAVR. Methods In this multicentre, retrospective, observational cohort study, patients with AF who underwent TAVR were included. The data was obtained from the Japanese multicentre registry, which comprises 19 centres from 2013 to 2019. Bleeding was defined as any post-discharge bleeding after TAVR. The primary endpoint was the incidence of all bleeding events in 3 populations: the overall population, the DOAC cohort, and the vitamin K antagonist (VKA) cohort. Results This study included 1230 patients with a mean age of 84.6 ± 5.1 years, of whom 457 were males. Among them, 465 patients (37.8%) were treated with a VKA while the rest were treated with a DOAC. Patients were divided into three groups according to their DOAC Score: 380 patients (30.1%) were in the ≤ moderate risk group with a DOAC Score of 7 or less, 497 patients (40.4%) were in the high-risk group with a DOAC Score of 8 or 9, and 353 patients (28.7%) were in the very high-risk group with a DOAC Score over 10. The cumulative incidence of all bleeding at 5 years in the overall population was significantly different in the 3 risk groups: ≤ moderate: 8.4%, high-risk: 10.8%, very high-risk: 21.6%, respectively (p< 0.01). The incidence was also significantly different in the DOAC and VKA cohorts (p<0.01 and p=0.03, respectively). Conclusion The recently published DOAC Score is well predictive of bleeding risk in Asian patients with AF after TAVR. The score may be useful in predicting bleeding in patients taking both DOAC and VKA.Graphical abstract