Heart failure with mid-range ejection fraction in CHARM: characteristics, outcomes and effect of candesartan across the entire ejection fraction spectrum

Abstract

Aims: We tested the hypothesis that candesartan improves outcomes in heart failure (HF) with mid-range ejection fraction [HFmrEF; ejection fraction (EF) 40-49%].

Methods and results: In 7598 patients enrolled in the CHARM Programme (HF across the spectrum of EF), we assessed characteristics, outcomes and treatment effect of candesartan according to EF. Patients with HFmrEF (n = 1322, 17%) were similar to those with HF with reduced EF (HFrEF; n = 4323, 57%) with respect to some characteristics, and intermediate between HFrEF and HF with preserved EF (HFpEF; n = 1953, 26%) with respect to others. Over a mean follow-up of 2.9 years, the incidence rates for the primary outcome of cardiovascular death or HF hospitalization were 15.9, 8.5 and 8.9 per 100 patient-years in HFrEF, HFmrEF and HFpEF. In adjusted analyses, the rates of the primary outcome declined with increasing EF up to 50%. For treatment effect, the incidence rates for the primary outcome for candesartan vs. placebo were 14.4 vs. 17.5 per 100 patient-years in HFrEF [hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.75-0.91; P < 0.001], 7.4 vs. 9.7 per 100 patient-years in HFmrEF (HR 0.76, 95% CI 0.61-0.96; P = 0.02), and 8.6 vs. 9.1 per 100 patient-years in HFpEF (HR 0.95, 95% CI 0.79-1.14; P = 0.57). For recurrent HF hospitalization, the incidence rate ratios were 0.68 in HFrEF (95% CI 0.58-0.80; P < 0.001), 0.48 in HFmrEF (95% CI 0.33-0.70; P < 0.001), and 0.78 in HFpEF (95% CI 0.59-1.03; P = 0.08). With EF as a continuous spline variable, candesartan significantly reduced the primary outcome until EF well over 50% and recurrent HF hospitalizations until EF well over 60%.

Conclusion: Candesartan improved outcomes in HFmrEF to a similar degree as in HFrEF. ClinicalTrials.gov: CHARM Alternative NCT00634400, CHARM Added NCT00634309, CHARM Preserved NCT00634712.

Keywords: Angiotensin receptor blocker; Candesartan; Heart failure; Mid-range ejection fraction; Outcomes; Preserved ejection fraction; Randomized controlled trial.