TGF-β1 is but one of an array of factors shown to be involved in the induction of cardiac fibrosis, as demonstrated in overexpression and knockout models.28, 29, 30 As atrial fibrillation is a serious clinical problem with high incidence in society31 and is linked to fibrosis of atrial tissues,32 we investigated whether or not there was an association between TGF-β1-induced fibrosis and autophagy in hATMyofbs. Here, TGFB1 is linked to atrial fibrillation.