BACKGROUND: Little is known about the recently emerging entity, heart failure with supranormal ejection fraction (HFsnEF). OBJECTIVE: To describe the clinical characteristics and outcome of HFsnEF, compared to HF with mildly reduced EF (HFmrEF) and HF with preserved EF (HFpEF) patients. DESIGN: A single center retrospective analysis. PATIENTS: Hospitalized and ambulatory heart failure (HF) patients who underwent echocardiography with left ventricular ejection fraction (LVEF) >
40%. MAIN MEASURES: Clinical and echocardiographic parameters, hospitalization rates and mortality. KEY RESULTS: A total of 6,202 patients (mean age 81.4 ± 14.1 years, 52% females) were analyzed: 750 in the HFmrEF group (LVEF 41-49%), 4360 in the HFpEF group (LVEF 50-64%), and 1092 in the HFsnEF group (LVEF ≥ 65%). Patients were followed for a median of 32 (11-65) months. HFsnEF patients were older, predominantly female, exhibited higher hypertension prevalence, more severe LV hypertrophy, smaller LV dimensions, and higher filling pressures compared to the other groups (p <
0.001 for all). These features were consistent in both hospitalized and ambulatory patients. In a univariable model, HFsnEF patients had higher mortality rates compared to HFmrEF and HFpEF patients (HR 1.258, 95% CI 1.117-1.418
p <
0.001 and HR 1.112, 95% CI 1.023-1.208
p = 0.012, respectively). However, in a multivariable model, adjusted for age, sex, comorbidities, and echocardiographic parameters, there was no significant difference in the mortality rates between all groups. The total hospitalization rate was similar between the HFpEF and HFsnEF groups, and lower in the HFmrEF group (p = 0.022). However, the HFsnEF group had the lowest rate of HF-related hospitalizations (p = 0.002). CONCLUSION: HFsnEF represents a group of patients with a distinct clinical and echocardiographic profile accompanied by worse outcomes, likely mediated by older age and a higher comorbidity burden, compared to HFmrEF and HFpEF. Therefore, the supranormal EF may serve as a marker rather than an independent prognostic factor.