ATRIOVENTRICULAR NODE AND HIS BUNDLE:
THIS is an example of the importance of anatomy. The .photos, all of them, illustrates the situation of the His bundle and atrioventricular node and the membranous septum. Take your time, an hour if you need,.
If you can incorporate this photo in your mind, you can close VSD, atrioventricular canal defects, do tricuspid valve replacements or you can also enjoy the anatomy.

Image #62