Abstract Body (Do not enter title and authors here): Background: The association between heart rate (HR) and clinical outcomes is well understood in patients with heart failure and reduced ejection fraction (HFrEF), but less clear in those with mildly reduced or preserved EF (HFmrEF/HFpEF), especially among individuals with atrial fibrillation (AF). In a prespecified analysis of the FINEARTS-HF trial, we investigated the association between baseline HR and clinical outcomes according to heart rhythm and evaluated the effect of finerenone across the HR spectrum in patients with HFmrEF/HFpEF.
Methods: FINEARTS-HF was a randomized, double-blind, multicenter, event-driven, trial in patients with left ventricular ejection fraction ≥40%, investigating the efficacy and safety of the non-steroidal mineralocorticoid receptor antagonist finerenone, compared to placebo, in HFmrEF/HFpEF. The primary outcome was the composite of cardiovascular death and total (first and recurrent) HF events (either an unplanned HF hospitalization or an urgent HF visit). Rhythm (sinus or AF) was determined from the baseline electrocardiogram (ECG); patients with pacemaker rhythm, missing ECG data, or missing HR records were excluded.
Results: Among patients with sinus rhythm (SR) (n=3,497, 62%), higher baseline HR was associated with a higher event rate of the primary outcome. In contrast, no association between HR and outcome was observed in patients with AF (n=2190, 38%) (Figure). This trend was also observed for the components of the primary outcome and all-cause death.
The effect of finerenone on the primary outcome (rate ratio, 0.84; 95% confidence
interval [CI], 0.74 to 0.95; P = 0.007) was consistent across the HR spectrum (Figure), regardless of rhythm (P for interaction=0.96 for SR; P for interaction=0.49 for AF). Consistent benefits were observed for the components of the primary outcome and all-cause death, irrespective of rhythm. There was no change in HR with finerenone, compared to placebo, in patients in SR. Finerenone led to a small but significant reduction in HR among patients with AF patients: placebo-corrected decrease 1.10 (95%CI: 0.22 to 2.20) bpm from randomization to 12 months.
Conclusion: In FINEARTS-HF, higher baseline HR was associated with a higher risk of primary outcome in patients with SR; however, no such association was observed in patients with AF. The effect of finerenone on the primary outcome was consistent across the HR spectrum, irrespective of rhythm.