Predictors of Left Ventricular Ejection Fraction Improvement in Patients with Early-Stage Heart Failure with Reduced Ejection Fraction.

Objectives: To identify the predictors of left ventricular ejection fraction (LVEF) recovery in patients with heart failure with reduced ejection fraction (HFrEF) and compare the mortality rate between patients with HFrEF and heart failure with improved ejection fraction (HFimpEF). Methods: Patients in a post-acute care program from 2018 to 2021 were enrolled. A series of echocardiograms were arranged during follow-up. Mortality, cardiovascular death and sudden cardiac death events were recorded. A total of 259 patients were enrolled and followed for at least 1 year; 158 (61%) patients fulfilled the criteria of HFimpEF, 87 (33.6%) were defined as having persistent HFrEF, and 14 (5.4%) were defined as having heart failure with mildly reduced ejection fraction. The patients with HFimpEF and persistent HFrEF were included for analysis. Results: The mean follow-up duration was 1090 ± 414 days, and the median time to LVEF recovery was 159 days (IQR 112-289 days). Multivariate logistic regression analysis showed that beta-blocker prescription was the only independent predictor of HFimpEF [odds ratio (OR) 2.11, 95% confidence interval (CI) 1.10-4.08, p = 0.03]. Diagnosis of ischemic cardiomyopathy (ICM) and QRS duration ≥ 110 ms were negative predictors of HFimpEF (OR 0.49, 95% CI 0.27-0.88, p = 0.02, and OR 0.4, 95% CI 0.21-0.77, p = 0.005, respectively). The patients with HfimpEF had a significantly better prognosis with lower mortality (hazard ratio 0.2, 95% CI 0.08-0.50, log-rank p < 0.001) than the patients with persistent HFrEF. Conclusions: Beta-blocker prescription was an independent predictor of HFimpEF, while the diagnosis of ICM and QRS duration ≥ 110 ms were negative predictors of HFimpEF. Patients with HfimpEF had a significantly lower mortality rate compared to those with persistent HFrEF.