Fig. 2.

Representative histopathological slides stained with hematoxylin–eosin of the junction site of the superior vena cava and right atrium (left panels), and left atrium near the left superior pulmonary vein orifice (right panels) in the control group and high-fat diet group. There are no histological abnormalities, i.e., fibrotic, inflammatory, hypertrophic, or fatty changes, in either group. Ganglion or nerve fiber bundles are seen in regions adjacent to the junction site of superior vena cava and right atrium, but no specific differences between the two groups are seen.