Subclinical atrial fibrillation and the risk of heart failure: insights from ARTESiA

Abstract Aims Heart failure (HF) and clinical atrial fibrillation are closely linked, but the relationship between device-detected subclinical atrial fibrillation (SCAF) and HF is unclear. We aimed to determine incidence and clinical risk factors for HF events among patients with SCAF. Methods We included 3986 patients from the ARTESiA (Apixaban for the Reduction of Thromboembolism in Patients with Device-Detected Subclinical Atrial Fibrillation) trial. ARTESiA investigated the effect of apixaban versus aspirin for stroke prevention in patients with episodes of SCAF ≤24 hours. In this secondary analysis, we explored the number and duration of SCAF episodes at baseline as risk markers for HF hospitalization or HF-related death. SCAF progression was analysed as a time-dependent covariate and defined as the development of SCAF 24 hours or clinical atrial fibrillation. Results Over a mean follow-up of 4.1 ± 1.7 years, SCAF progression was observed in 1244 patients (31%). Heart failure hospitalization or HF-related death occurred in 515 (13%) patients at a rate of 3.3 95% confidence interval (CI) 3.1-3.6 per 100 person-years. A total of 172 HF-related events occurred after SCAF progression (7.2 events, 95% CI 6.2-8.3, per 100 PY). SCAF progression was an independent risk factor for HF hospitalization or HF-related death (hazard ratio 2.72, 95% CI 2.24-3.31). Conclusion Heart failure hospitalization and HF-related death are common in patients with SCAF. Progression to longer SCAF episodes or clinical AF were associated with HF events, but episodes 24 h were not. These findings underscore the need for close surveillance of SCAF patients to detect complications and potentially improve outcomes.