Safety and effectiveness of direct oral anticoagulants in AF patients with nonmechanical valves

Abstract

Background: Direct oral anticoagulants (DOACs) have been studied in nonvalvular atrial fibrillation (AF) (NVAF). Data are lacking in patients with nonmechanical valvular (NMV) AF.

Objective: We hypothesized that DOACs were safe and effective in patients with NMV AF.

Methods: A retrospective cohort study was designed within administrative health care databases. The cohort entry date was the first DOAC dispensation or 3 months after the NMV procedures. Follow-up was until the end of data availability or exposure to DOACs. The primary outcome was ischemic stroke or embolism. The secondary outcome was major bleeding. Event rates were compared with those in patients with NVAF in the same databases and included in a meta-analysis.

Results: A total of 692 patients were included. Of those, 100 patients (14.4%) received dabigatran, 229 (33.1%) rivaroxaban, and 363 (52.5%) apixaban. Owing to low event incidence, data were pooled. There were 7 ischemic strokes/embolisms in 699 person-years, an incidence rate of 1.00 per 100 person-years (95% confidence interval [CI] 0.48-2.10), and 12 major bleedings in 689 person-years, an incidence rate of 1.74 per 100 person-years (95% CI 0.99-3.07). NVAF cohorts demonstrated 554 ischemic strokes/embolisms in 6707.58 person-years, an incidence rate of 0.83 per 100 person-years (95% CI 0.76-0.90; P = .613), and 1907 major bleedings in 64,178.27 person-years, an incidence rate of 2.97 per 100 person-years (95% CI 2.84-3.11; P = .065). Event rates were overlapping with other studies.

Conclusion: This is the largest cohort of patients with NMV AF and DOACs to be described. Based on low event rates, our data support the prescribing of DOACs in this population.

Keywords: Anticoagulants; Atrial fibrillation; Bleeding; Nonmechanical valves; Thromboembolic events.