Although vimentin was used in this study to stain fibroblasts and results showed no difference in the amount of fibroblasts between A-TP and control animals, our findings do not differ from those of Lugenbiel et al., where a 3-fold increase of α-SMA expressing cells (myofibroblasts) was found despite similar amounts of vimentin in AF and control pigs (25). Here, ACTA1 is linked to atrial fibrillation.