This study focuses on The most commonly used outcome in clinical trials in patients with heart failure and reduced ejection fraction (HFrEF) is the composite of time to hospitalization for worsening heart failure or cardiovascular death, whichever occurs first.1–4 In recent years there has been a major effort to reduce the rate of hospital admission by treating worsening heart failure outside the traditional inpatient ward setting. This was recognized in the updated Standardized Data Collection for Cardiovascular Trials Initiative cardiovascular and stroke end point definitions for clinical trials that included episodes of worsening heart failure if they resulted in intravenous treatment.5–7 However, such events are infrequent, even in contemporary trials.8–11 Many more patients are treated for worsening symptoms and signs in the community by means of the augmentation of oral therapy.11,12 The frequency and prognostic importance of such nonhospitalized episodes of worsening, treated with oral therapy, is not clear, in part, because these episodes have not been recorded in many trials and, where they have been recorded, such events have not been sought systematically or defined in a consistent way. 8–12 In the placebo-controlled DAPA-HF trial (Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure), dapagliflozin, added to other guideline-recommended therapies, reduced the risk of mortality and heart failure hospitalization, and improved symptoms in 4744 patients with HFrEF.

Reference-https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.120.047480