SLC8A1 and hydrops fetalis: It has been shown that with the development of HF, there is a decrease in Ca2+ transport to the sarcoplasmic reticulum (SR) by the SR Ca2+-ATPase (SERCA2a), an increase in Ca2+ efflux by the Na2+/Ca2+ exchanger (NCX1) and dysfunction of the SR Ca2+ channels (ryanodine receptors-RyRs), leading to diastolic Ca2+ leak from the SR [20,21,22].