Parietal limb of septomarginal trabecula

The septomarginal trabecula (mderator band) presents two limbs.

• The parietal limb of the septomarginal trabecula is the posteroinferior limb and supports the muscular septum, and the medial papillary muscle typically originates from this section, contributing to the stability and function of the tricuspid valve.

• The anterior limb of the septomarginal trabecula runs up to the attachment of the pulmonary valve leaflets. It is integral to the structure of the right ventricle, ensuring proper alignment and function of the outflow tract.

Note that their names and definitions considerably vary between sources.