Another example for such an unfavorable trade-off in FGF23 biology is left ventricular hypertrophy.51 Similar to volume expansion, cardiomyocyte hypertrophy is effective in enhancing cardiac output transiently but may ultimately result in heart failure over the long run (C/B > 1).52 As such, FGF23 might represent a promising pharmacological target to attenuate pathological changes elicited by its excessive overproduction. The gene discussed is FGF23; the disease is heart failure.