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.