This methodology was taken from our previous study (12). All animals were sacrificed 3 weeks after MI induction, after the echocardiography study. Hearts were collected and cryopreserved in OCT compound. Heart sections (10 μm thick) were cut from the apex to the height of the ligation. Each section was cut at 100-μm intervals. Masson’s trichrome [HT15 Trichrome Staining (Masson) Kit, Sigma-Aldrich] staining was performed according to the manufacturer’s specifications. A PathScan Enabler IV slide scanner (Advanced Imaging Concepts, Princeton, NJ) was used to acquire images of each stained section. These were used to assess morphometric parameters (i.e., infarct thickness and viable myocardium), which were quantified with NIH ImageJ software.