The three subtypes of heart failure are HF with reduced left ventricular ejection fraction (HFrEF) EF <40% (amended to ≤ 35%), HF with preserved LVEF (HFpEF) in patients with an EF greater than 50%, LV diastolic dysfunction, and evidence of structural heart disease (HFmrEF) in patients with an LVEF of 40-49%, diastolic dysfunction, increased BNP concentrations, and evidence of structural heart disease [4, 5]. The gene discussed is NPPB; the disease is hydrops fetalis.