However, there is a disconnect between these observations and previous studies reporting increased myocardial CNP release and plasma CNP levels in patients with HF.17–19 Whether this results from the short-term nature of the experimental model utilized herein, and that more chronic release of CNP (as an intrinsic protective mechanism) is required to sustain elevated plasma concentrations, remains to be clarified. This evidence concerns the gene CNP and hydrops fetalis.