Abstract 16829: Stringency of Rate Control in Patients with Atrial Fibrillation and Heart Failure: Data of the Rate Control Efficacy in Permanent Atrial Fibrillation: a Comparison between Lenient versus Strict Rate Control II (RACE II) Study
Introduction: The RAte Control Efficacy in permanent atrial fibrillation (AF) II (RACE II) trial showed that lenient rate control is not inferior to strict rate control in the treatment of permanent AF. Whether this also holds for patients with heart failure (HF) is unknown.
Hypothesis: We hypothesized that lenient rate control is comparable to strict rate control in patients with moderate HF for preventing cardiovascular morbidity and mortality.
Methods: In RACE II 614 patients with permanent AF <12 months were randomized to lenient (resting heart rate <110 bpm) or strict rate control (resting heart rate <80 bpm and heart rate during moderate exercise <110 bpm). Included in this predefined subanalysis were patients with either a left ventricular ejection fraction (LVEF) <40% at baseline, or prior hospitalization for HF. Primary outcome was a composite endpoint for cardiovascular morbidity and mortality.
Results: One-hundred-sixteen (19%) patients with HF were identified, mean age 68±9 years, 79 male (68%). Fifty percent was classified as NYHA class II or higher. At baseline, left atrial size (48±7 vs. 46±7, p=0.003) and LV end diastolic (55±7 vs. 50±7, p=<0.001) and end systolic dimensions (43±9 vs. 35±7, p=<0.001) were significantly larger and LVEF significantly lower (38±13 vs. 55±9, p=<0.001) in the HF compared to non-HF patients. Fifty-five patients were randomized to lenient and 61 to strict rate control. At end of the dose-adjustment phase rate control target was achieved in 94.6% and 73.8% in the lenient and strict group, respectively (p=0.003), with less visits in the lenient group (0 [IQR 0–0] vs. 2 [IQR 1–3], p=<0.001). Mean (±SD) resting heart rate was 97±13 and 76±13 (lenient and strict group, respectively, p=<0.001). The estimated cumulative incidence of the primary outcome at 3 years was 18.6% in the lenient and 20.6% in the strict group (p=0.9).
Conclusions: In patients with permanent AF and moderate HF lenient rate control is as effective as strict rate control and easier to achieve. Therefore, lenient rate control can also be considered in these patients.
- © 2010 by American Heart Association, Inc.