When calcium homeostasis occurs in patients with HF, the intracellular Ca2+ homeostatic order will cause contraction and diastolic dysfunction by interfering with RyR2, the sarcoplasmic Ca2+-ATP enzyme (SERCA) pathway, and the sodium/calcium exchange protein (NCX) (144, 145), resulting in the development of HF. This evidence concerns the gene RYR2 and hydrops fetalis.