TMAO also increased the expression levels of atrial natriuretic factor (ANP) and β‐myosin heavy chain (β‐MHC), which caused myocardial hypertrophy and fibrosis through activation of the TGF‐β1/Smad3 pathway (Li, Wu, et al. 2019) (Figure 3). This evidence concerns the gene NPPA and cardiac hypertrophy.