Both sacubitril/valsartan and valsartan treatment remarkably abrogated the upregulated protein expression of TGF-β1 and p-Smad3 observed in infarcted myocardium of MI rats, and the inhibitory effect of sacubitril/valsartan was significantly better than that of valsartan (p < 0.05). Here, SMAD3 is linked to myocardial infarction.