The Distribution of Left Ventricular Ejection Fraction, Characteristics, and Clinical Outcomes of Patients with Newly Diagnosed Heart Failure in Taiwan.

Data regarding the distribution of left ventricular ejection fraction among patients with newly diagnosed heart failure (HF) and the outcomes of patients with heart failure with preserved ejection fraction (HFpEF) in Taiwan are limited. Patients with newly diagnosed HF were identified from a multi-institutional database between 2016 and 2020. Outcomes were compared between patients with HFpEF and heart failure with reduced ejection fraction (HFrEF) after propensity score matching (PSM). Of 7,736 newly diagnosed HF patients, 4,393 (56.8%) had HFpEF and 1,977 (25.6%) had HFrEF. The HFpEF group was older (71.5 vs. 64.2 years) and more likely to be female (48.9% vs. 31.1%). Comorbidities were more common in the HFpEF patients. Median follow-up was 2.1 years. Prior to PSM, the HFpEF patients had higher all-cause mortality risk [hazard ratio (HR) 1.21, 95% confidence interval (CI) 1.11-1.33] but lower cardiovascular (CV) death risk (HR 0.84, 95% CI 0.72-0.97) compared to those with HFrEF. The HFpEF group had a trend of higher overall hospitalization risk (HR 1.06, 95% CI 0.99-1.14), but lower HF hospitalization risk (HR 0.61, 95% CI 0.55- 0.67). After PSM, all-cause mortality and overall hospitalization were comparable. The HFpEF group had lower rates of CV death (HR 0.82, 95% CI 0.68-1.0) and HF hospitalization (HR 0.60, 95% CI 0.53-0.69) compared to the HFrEF group. Among patients with newly diagnosed HF, HFpEF is the predominant phenotype, characterized by older age, higher female prevalence, and increased comorbidities. After adjusting for these factors, all-cause death and hospitalization risks became similar between the HFpEF and HFrEF patients. The HFpEF patients had lower risks of CV death and HF hospitalization.