A Narrative Review on the Efficacy and Safety of Loop Diuretics in Patients With Heart Failure With Reduced Ejection Fraction and Preserved Ejection Fraction

To date, loop diuretics are the mainstay treatment for decongestion in patients with acute decompensated heart failure (HF). In clinical practice, loop diuretics have also been utilized for patients with chronic HF with reduced and preserved ejection fractions. There is a paucity of quality evidence of the effect of loop diuretics use and dosing on clinical outcomes in HF patients beyond symptomatic relief. In this review, we aimed to summarize recently published data on the use of loop diuretics in patients with HF, focusing on efficacy and safety outcomes in patients with HF with reduced and preserved ejection fraction. We searched EMBASE, PubMed, CINAHL, and the "Web of Science" databases. Cohort studies and randomized controlled trials published after 2018 and written in English were included in this review. Case reports, case series, cross-sectional studies, review articles, commentaries, articles published more than five years ago, and studies involving children were excluded. Results were divided into the efficacy and safety of loop diuretics in HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF). A registry-based study included in our review observed a reduced 30-day all-cause mortality in patients with HFrEF receiving loop diuretics compared to those not receiving loop diuretics (HR=0.73; 95% CI=0.57-0.94; p=0.016), but there was no statistically significant association at the 60-day follow-up of the same group of patients. Most studies reviewed showed that the choice of loop diuretics did not influence clinical outcomes such as mortality and HF rehospitalization in patients with HF with reduced and preserved ejection fraction despite differences in oral bioavailability and half-life. Studies have consistently shown that patients with HF who receive a higher dose of loop diuretics are likely to experience a decline in renal function and hypotension, regardless of their type of HF. Discontinuation or reduction of the dose of loop diuretics should be considered in patients with HF after decongestion.