The Emperor-Preserved trial: what will change for patients with heart failure with preserved ejection fraction?

Abstract

With the presentation of the Emperor-Preserved trial at the 2021 European Society of Cardiology (ESC) Congress and its subsequent publication [1], the cardiology world breathed a sigh of relief that – at last – a drug had been shown to improve outcomes in patients with heart failure with preserved ejection fraction (HFpEF). The primary composite endpoint of cardiovascular death and HF hospitalisation was reduced in patients on empagliflozin compared to placebo (Hazard ratio [HR] 0.79; 95% CI 0.69 – 0.90, p < 0.001), driven by a significant decrease in HF hospitalisation (HR 0.71, 95% CI 0.60 – 0.83, p < 0.001). Cardiovascular death was not significantly different between groups. The result was irrespective of diabetes status. All-cause mortality was identical for the empagliflozin and placebo groups: 14.1% and 14.3% respectively, and all-cause hospitalisation was not reduced by empagliflozin. Two-thirds of the sample met the ESC criterion for ejection fraction (EF) > 50% as one of the criteria for HFpEF, while 33% had an EF in the mildly reduced range (40 – 49%). Sub-group analyses by EF showed a diminution of effect as EF increased, so that above 60% the HR was not significant (0.87, 95% CI 0.69 – 1.10).