TGFB1 and atrial fibrillation: - Obese (vs. lean): ↑ LA volume, ↑ LA pressure, ↓ CV, ↑ CV heterogeneity, ↔ ERP, ↔ ERP heterogeneity, ↑ AF burden, ↑ epicardial fat infiltrate in posterior LA and ↓ voltage in this region, ↑ atrial fibrosis and TGF-β