Heart Failure With Stable Mildly-reduced Ejection Fraction: Prognosis and Predictors of Outcomes

Heart failure with mildly-reduced ejection fraction (HFmrEF) of 40%-49% is an under-recognized type of heart failure. The prognosis and predictors of outcomes of stable mildly-reduced ejection fraction (EF) of 1 year are unclear. This is a retrospective study. Included patients had stable left ventricular ejection fraction (LVEF) for at least 1 year (n = 609) and were classified into 3 groups based on LVEF. Clinical outcome measures were all-cause mortality, cardiac mortality, and HF hospitalization (HFH). In patients with stable HFmrEF of one year, the predictors of clinical outcomes and hospital length of stay (LOS) were studied. Patients with stable HFmrEF had lower HFH rate compared to stable HFrEF with HR = 0.52 (95% CI = 0.39-0.70), P = 0.0001, and a higher HFH rate compared to stable HFpEF with HR = 1.23 (95% CI = 1.01-1.50), P = 0.032. Mortality rates were similar between all groups. In the stable HFmrEF patients, beta-blockers caused lower cardiac mortality, and CKD had fewer HFH. Unfavorable predictors were loop diuretics for mortality, and higher NYHA class for HFH. Smoking and CKD were associated with a longer hospital stay. Stable HFmrEF patients with at least one HF admission had higher mortality. Patients with stable HFmrEF had a lower HFH rate compared to stable HFrEF and higher HFH rate compared to stable HFpEF. In patients with stable HFmrEF, CKD, NYHA class, beta-blockers, and loop diuretics were predictors of clinical outcomes. Smoking and CKD were predictors of hospital LOS.