Serum FGF21 levels were not significantly correlated with gender, previous hypertension, diabetes mellitus, history of AF, total blood cholesterol, triglycerides, uric acid, creatinine levels, pulmonary artery pressure, mitral regurgitation, LAD, IVST, LVPWT, LVEDV, LVM, and coronary multiple lesions. Here, FGF21 is linked to mitral valve insufficiency.