FGF23 and chronic kidney disease: Elevations of circulating FGF23 levels during CKD progression are independently associated with cardiovascular mortality, possibly via direct and potentially reversible effects of FGF23 on cardiac myocytes that culminates in LVH.11–15 Indeed, mortality due to cardiovascular disease is extremely high among patients with CKD.7,8,10 However, the direct role of FGF23 in CKD-associated cardiac hypertrophy is currently under debate.