Trabeculae carneae

The trabeculae carneae (columnae carneae, or meaty ridges), are rounded or irregular muscular columns which project from the inner surface of the right and left ventricles of the heart.^[1] These are different from the pectinate muscles, which are present in the right atrium and the atrial appendages of the heart.

Types

There are two kinds:

• some are attached along their entire length on one side and merely form prominent ridges,
• others are fixed at their extremities but free in the middle (Moderator bands/septomarginal trabeculae).

Function

The purpose of the trabeculae carneae is most likely to prevent suction that would occur with a flat surfaced membrane and thus impair the heart's ability to pump efficiently.

The trabeculae carneae also serve a function similar to that of papillary muscles in that their contraction pulls on the chordae tendineae, preventing inversion of the mitral (bicuspid) and tricuspid valves, that is, their bulging towards the atrial chambers, which would lead to subsequent leakage of the blood into the atria. So by the action of papillary muscles on the atrioventricular valves, backflow of the blood from the ventricles into the atria is prevented.

The moderator bands carry the right branch of the AV bundle and are part of the conducting system of the heart.

See also

• Trabecula

References

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)

External links

• -1033174980 at GPnotebook
• thoraxlesson4 at The Anatomy Lesson by Wesley Norman (Georgetown University) (heartinternalstructures - "TC" on diagram)
• Diagram at University of Edinburgh -- fourth and fifth diagrams from top