NPPB and hydrops fetalis: Both BNP and NT-proBNP (NT-proBNP is the inactive part of the hormone proBNP, secreted by cardiomyocytes due to wall stress) appear to have similar predictive value in HF,3,5 but NT-proBNP has less biological variation than BNP and greater stability when stored at room temperature in EDTA plasma.4,6–11 Unlike BNP assays, many NT-proBNP assays use the same antibodies, so results from different manufacturers show greater agreement.12 For these reasons, NT-proBNP is an attractive target for routine monitoring of HF in the community.