TGFB1 and atrial fibrillation: The postulated mechanisms by which mechanical LA substrate formation with chronic alcohol consumption may trigger atrial arrhythmias that are attributable to accumulative oxidative damage and fibrotic replacement (e.g., upregulated TGF-β1/collagen) within atrial myofibers, which may interfere with electrical conduction, promoting and perpetuating AF [23,35].