The nightmare case for a Ross procedure. The first septal artery is unique and very large and merges from the very nadir of the non facing pulmonary leaflet. This septal artery supplies the moderator band. The right bundle branch is seen and marked with a silver bead.
1: septum
mb: moderator band
Pv: pulmonary valve
2: anterior and septal leaflets of the tricuspid valve

Image #160