NPPB and hydrops fetalis: As the widely admitted biomarker in HF, NT-proBNP quantitatively reflects hemodynamic myocardial stress (19), indicating not only left ventricular (LV) systolic dysfunction but also cardiac abnormalities, such as LV diastolic dysfunction, right ventricular (RV) dysfunction, valvular dysfunction, increased pulmonary pressures, and atrial arrhythmias.