Clinical Benefit of Direct Oral Anticoagulants Versus Vitamin K Antagonists in Patients with Atrial Fibrillation and Bioprosthetic Heart Valves.

Purpose: The use of direct oral anticoagulants (DOACs) in patients with atrial fibrillation (AF) and bioprosthetic heart valve is still controversial. The aim of this study was to compare the tolerability and effectiveness of treatment with DOACs versus vitamin K antagonists (VKAs) in patients with AF and a bioprosthetic heart valve in clinical practice.
Methods: Data for this study were sourced from the multicenter, prospectively maintained AF Research Database (NCT03760874), which includes all patients with AF undergoing follow-up at participating centers through outpatient visits every 3-6 months. The rates of occurrence of thromboembolic events (ischemic stroke, transient ischemic attack, systemic embolism), major bleed, and intracranial hemorrhage (ICH) were assessed. These data were used for quantifying the net clinical benefit (NCB) of DOACs versus VKAs, in accordance with the following formula: (Thromboembolic events incidence rate with VKAs - Thromboembolic events incidence rate with DOACs) - Weighting factor × (ICH rate with DOACs - ICH incidence rate with VKAs). The database was retrospectively queried for patients with AF who were prescribed a DOAC or VKA and had a history of bioprosthetic heart valve replacement.
Findings: A total of 434 patients with AF (DOACs, n = 211; VKAs, n = 223) were identified. Propensity score matching identified 130 patients prescribed DOACs (apixaban, 55.4%; rivaroxaban, 30.0%; dabigatran, 13.1%; edoxaban, 1.4%) and the same number of VKA recipients (warfarin, 89.2%; acenocoumarol, 10.8%). The mean (SD) duration of follow-up was 26.8 (2.3) months. The incidence rates of thromboembolic events were 1.3 per 100 person-years in the DOAC group versus 2.0 per 100 person-years in the VKA group (P = 0.14). The incidence rates of major bleed events were 2.6 per 100 person-years in the DOAC group versus 4.9 per 100 person-years in the VKA group (P = 0.47). The incidence rates of ICH were 0.38 per 100 person-years in the DOAC group versus 1.16 in the VKA group (hazard ratio = 0.33; 95% CI, 0.05-2.34; P = 0.3). A positive NCB of DOACs over VKAs of +1.87 was found.
Implications: According to these data from clinical practice, DOACs seem to be associated with a greater NCB versus VKAs in patients with AF with a bioprosthetic heart valve, primarily due to lower rates of both major bleeds and thromboembolic events.
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