First-phase ejection fraction to predict adverse outcomes in patients with heart failure.

Background: First-phase ejection fraction (EF1) is a novel measurement of early left ventricular systolic dysfunction. We investigate its prognostic value in patients with heart failure (HF).

Methods And Results: Patients with HF were prospectively enrolled from July 2019 to September 2021. A total of 228 patients were included in the final analysis. The primary endpoint was the composite of all-cause mortality or rehospitalization for HF, which occurred in 74 patients (32.46%). EF1 as well as other parameters for left ventricular function were measured in echocardiography. Time-dependent ROC showed the cutoff value of EF1 was 18.55%. Kaplan-Meier analysis indicated a higher rate of adverse events in the lower EF1 group (EF1 ≤ 18.55%) (Log-rank test P < 0.001). Cox regression analyses showed EF1 was an independent predictor with adverse events as a continuous variable (Cox model 1: per 1% change in EF1: HR = 0.92, 95%CI: 0.87-0.97, P < 0.001), as well as a categorical variable (Cox model 2: EF1 > 18.55%: HR = 0.21, 95%CI: 0.08-0.53, P < 0.001) after adjustment for hypertension, coronary artery disease (CAD), Log10 (NT-proBNP), eGFR, E/e' and loop diuretics. Restricted cubic splines revealed a linear association between EF1 levels and the incidence of adverse events (P for non-linearity = 0.145). The subgroup analyses showed the predictive ability of elevated EF1 on the decreased risk of adverse events did not change substantially stratified by HF classification, age, CAD and hypertension.

Conclusion: EF1, as a novel measurement of early systolic function, is a promising predictor of adverse events among HF patients. EF1 might be considered a new measurement for risk stratification of HF.