The exact mechanism of how FGF-23 is linked to CV death in AF is yet to be established but could include induction of left ventricular hypertrophy and cardiac remodelling,32 a mechanism that might in fact be reversible by therapeutic interventions.33 Further studies are needed to clarify the role of FGF-23 in cardiovascular disease and AF. Here, FGF23 is linked to left ventricular hypertrophy.