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] They should not be confused with the pectinate muscles, which are present in the right atrium and the auricles of the heart.

Types

They are of three 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,
• while a third set, the papillary muscles are continuous by their bases with the wall of the ventricle, while their apices give origin to the chordæ tendineæ which pass to be attached to the segments of both the bicuspid valve (mitral valve, or left atrioventricular valve) and the tricuspid valve (right atrioventricular valve).

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.

See also

• Trabecula

References

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

This article incorporates text from a public domain edition of Gray's Anatomy.