Since ARNi therapy was predominantly started in stable patients because of fear of hypotension, the PIONEER-HF (Comparison of Sacubitril-Valsartan versus Enalapril on Effect on NT-proBNP in Patients Stabilised from an Acute Heart Failure Episode) evaluated the efficacy and safety in unstable patients, who were hospitalised for acute decompensated heart failure (ADHF) [19]. Here, NPPB is linked to hydrops fetalis.