LVEF deterioration into midrange levels increases risk of adverse outcomes in HFmrEF
Association of Prior Left Ventricular Ejection Fraction With Clinical Outcomes in Patients With Heart Failure With Midrange Ejection Fraction
Introduction and methods
Many trials investigating HF therapies have excluded patients with heart failure (HF) with midrange ejection fraction (HFmrEF, LVEF between 40% and 50%). Therefore, less information is known about clinical characteristics of patients with HFmrEF, compared to patients with HF with preserved ejection fraction (HFpEF, LVEF of 50% or greater) and patients with HF with reduced ejection fraction (HFrEF, LVEF less than 40%) [1-3]. Transition into the HFmrEF category can occur by improvement from a previously reduced LVEF, or deterioration from a previously normal LVEF. This retrospective cohort study evaluated whether risk of future events in HFmrEF patients was affected by directional change in LVEF from a prior measurement.
A total of 448 adults with documented HFmrEF were included in this analysis. All enrolled patients had a documented LVEF from 40% to 50% measured by transthoracic echocardiography (TTE) and at least one prior TTE for comparison that was performed at least 3 months before index study. Patients were categorized based on whether their LVEF had either improved from a prior LVEF of less than 40% (improved group, n=157, 35%), remained stable between 40% and 50% (stable group, n=67, 15%) or deteriorated from a prior LVEF greater than 50% (deteriorated group, n=224, 50%).
Studied outcomes were the composite of all-cause mortality and all-cause hospitalization, the composite of CV mortality and HF hospitalization, and each of the individual components. Median follow-up was 2.24 (IQR 1.87-2.53) years.
- Patients in the deteriorated group had an increased risk of the composite outcome of all-cause mortality and all-cause hospitalization compared with patients in the improved group (HR 1.34, 95%CI 1.10-1.82, P=0.03). This difference was maintained with multivariable analysis.
- When looking at individual outcomes, a trend towards increased risk of all-cause mortality (HR 1.48, 95%CI 0.96-2.23, P=0.08) and all-cause hospitalization (HR 1.31, 95%CI 0.99-1.80, P=0.06) was observed in the deteriorated group compared to the improved group.
- Patients in the deteriorated group also had an increased risk of the composite outcome of CV mortality and HF hospitalization (HR 1.71, 95%CI 1.08-2.50, P=0.02), compared to patients in the improved group. This difference was also maintained with multivariable analysis. On the individual outcomes, a trend towards higher risk of CV mortality was observed in the deteriorated group compared to the improved group (HR 1.90, 95%CI 0.95-3.78, P=0.07). No difference in risk of HF hospitalization was observed between groups.
- No significant differences in any of the studied outcomes were observed between the improved group and stable group.
Patients whose LVEF deteriorated from greater than 50% to the 40% to 50% range had a significantly higher risk of the composite outcome of all-cause mortality and all-cause hospitalization and the composite of CV mortality and HF hospitalization, compared to those whose LVEF had improved from a lower value. These findings emphasize the need for careful follow-up of patients with HFmrEF.