NPPA and hydrops fetalis: Pathological cardiac remodeling and HF is typically associated with i) changes in the cardiac molecular signature (e.g. increased expression of cardiac fetal genes including atrial natriuretic peptide (Anp) and B-type natriuretic peptide (Bnp), as well as decreased expression of genes important for maintaining cardiac function such as sarcoplasmic reticulum Ca2+ ATPase (Serca2a) and alpha myosin heavy chain (αMHC)), and ii) increased deposition of collagen (fibrosis) in the extracellular matrix which makes the heart stiff [32–35].