Increased function of KDM4A causes an intensification of cardiac hypertrophy in response to pressure overload exposure, mediated by demethylation of histone 3-lysine 9 (H3K9) residues and activation of genes such as ANP, BNP, and four and a half LIM domain (FHL1) which are essential for the development of hypertrophy in rats. Here, KDM4A is linked to cardiac hypertrophy.