Anatomic locations of ventricular septal defects

Left panel: The ventricular septum, viewed from the right ventricular side (left panel), is made up of four components: the inlet (I) extends from the tricuspid annulus to attachments of the tricuspid valve; the trabecular septum (T) extends from inlet out to apex and up to smooth-walled outlet; the outlet (O) or infundibular septum extends up to the pulmonary valve; and the membranous septum.
Right panel: The anatomic location of ventricular septal defects.