“…Several studies investigated the implications of biomarkers such as TGF-β1, ferritin, PTH, CA -125, micro RNAs, N-terminal pro-B type natriuretic peptide (NT-proBNP), and b type natriuretic peptide (BNP) as a surrogate marker of fibrosis in AF patients [18][19][20][21][22]. Also, FGF-21 and FGF-23, members of the fibroblast growth factor family, were evaluated in previous studies for their levels in patients with AF [23,24].…”