TTN and hydrops fetalis: In HF, the RyR2 receptors are hyperphosphorylated (Lehnart et al. 2004) and many myofilament proteins (such as cTnI, cMyBP-C, and titin) are hypophosphorylated (Hamdani et al. 2008; Solaro 2008; Solaro and de Tombe 2008) (with an exception of some phospho-sites on titin that become hyperphosphorylated when they are targeted by PKC and CaMKII, two kinases upregulated in HF) (Hamdani et al. 2013b).