FGF23 and atrial fibrillation: In this context, several are the biomarkers identified and tested for risk stratification of AF, including the C-reactive protein (CRP) [38], the fibroblast growth factor-23 (FGF-23) [39], the high sensitivity troponin I [40], Galectin-3 [41], the N-terminal pro-B-type natriuretic peptide (NT-proBNP) [38, 39, 42–44], and several micro-RNAs [45].