The two fibrotic biomarkers of TGF-β1 and PIIINP are found to be associated with extensive myocardial fibrosis, especially atrial fibrosis, and previous studies report increased levels of these two biomarkers in patients with AF and coexisting cardiovascular disease or baseline before onset of AF [2, 5, 6, 9, 10, 22, 36]. Here, TGFB1 is linked to cardiovascular disorder.