*2.6. Histological Evaluation*

Hearts were fixed in 4% paraformaldehyde, and then paraffin-embedded and cut into 5 μm sections. Cardiac sections were stained with FITC-labeled wheat germ agglutinin for the analysis of cardiomyocyte size. At least 10 random areas of the heart were measured and only cardiomyocytes with well-defined borders and visible nuclei were used. Images were obtained by the Zeiss LSM 880 Airyscan confocal microscope (Zeiss, Oberkochen, Germany) and analyzed using Image J software. Fibrotic tissue was visualized by staining with picrosirius red according to a standard protocol. Total collagen was quantified using ImageJ software and was expressed as the ratio of collagen-stained area to total muscle area of the left ventricle and septum. All histological images were analyzed by two independent investigators in a blinded manner.
