NPPB and hydrops fetalis: Several pathways involved in maintaining and driving the progression of HF have been identified, including activation of the neurohormonal axis, inflammation, oxidative stress, myocardial injury, fibrosis, and matrix remodeling.2, 6 However, beyond the use of natriuretic peptides (NT-proBNP or BNP)—indicators of myocyte stress and right ventricular function, the clinical management in the European Society of Cardiology (ESC)/European Respiratory Society (ERS) guidelines of HF and PH have not yet endorsed the use of other biomarkers representative of other mechanisms.4, 7