Findings Across the Ejection Fraction Subgroups in Hospitalised Heart Failure Patients: The First MY-HF Registry Study

Background: Three main phenotypes describe heart failure (HF) according to left ventricular ejection fraction (LVEF). This study aims to describe the characteristics, management and outcomes of hospitalised patients with HF categorised by LVEF. Methods: The Malaysian National Heart Failure (MY-HF) Registry is a 3-year prospective, observational study of patients admitted for acute HF. This analysis includes 2,651 patients categorised into: HF with reduced ejection fraction (HFrEF; LVEF ≤40%), HF with mildly reduced ejection fraction (HFmrEF; LVEF 41−49%) and HF with preserved ejection fraction (HFpEF; LVEF ≥50%). Hospital readmission and mortality outcomes at 30 days and 1 year were examined. Results: The HFrEF subgroup represented the largest proportion of patients (66.2%), followed by HFpEF (22.1%) and HFmrEF (11.7%). The HFpEF subgroup was older (mean age 65.3 ± 13.3 years), had the highest proportion of females (53.5%) and had more patients with de novo HF at admission than the HFrEF subgroup (41.9% versus 31.4%). Comorbidities, such as hypertension, AF and chronic kidney disease, were more prevalent in the HFpEF than HFrEF subgroup. Conversely, more HFrEF patients had ischaemic heart disease and elevated N-terminal pro B-type natriuretic peptide levels (≥1,000 pg/ml). Similar 30-day and 1-year outcome rates were observed across the subgroups except for lower 30-day hospital readmission (p=0.024) and 1-year mortality (p=0.005) in the HFpEF subgroup. Older age (>60 years) and New York Heart Association class III–IV increased 1-year readmission risk. Conclusion: The MY-HF Registry highlighted high 1-year mortality in patients with HF, especially those with advanced NYHA class or chronic kidney disease. This suggests potential areas for improvement in HF management, including medication regimens, adherence and comorbidity management. Future research exploring these factors could significantly impact clinical practice and patient outcomes.