NPPB and hydrops fetalis: In the PIONEER-HF (Comparison Of Sacubitril/valsartan Versus Enalapril on Effect on NT-pro-BNP in Patients Stabilized From an Acute Heart Failure Episode) trial, patients with acute HF and elevated natriuretic peptides (> 1,500 pg/mL) randomized to sacubitril/valsartan while still admitted to the hospital had a greater reduction in aminoterminal pro-B-type natriuretic peptide (NT-proBNP) levels from baseline to weeks 4 and 8 compared to those receiving enalapril, with trends towards improved clinical outcomes [58].