For example, the nuclear occupancy of NFAT4 was increased in heart failure.28 Inhibiting the calcineurin-NFAT pathway protects the heart from excessive cardiac remodeling.29 NFAT4 activation also contributes to hypertension and increased wall thickness in the heart.30 Our present work for the first time reveals the function of NFAT4 in cardiomyocyte mitochondrial fission and apoptosis. This evidence concerns the gene NFATC3 and heart failure.