NPPB and hydrops fetalis: HFpEF is defined as a complex of signs and symptoms typical for HF: left ventricular ejection fraction >50%, elevated levels of brain natriuretic peptides (BNP > 35 pg·ml−1 and/or NT-proBNP > 125 pg·ml−1), and objective evidence of structural heart disease and/or diastolic dysfunction usually provided by echocardiography.