QS Study

Trabeculae Carneae

These are the muscular ridges present in the interior of e inflowing part of the ventricle. They are the smallest naturally arising collections of linearly arranged myocytes in the heart. They are one of the irregular bands and bundles of muscle projecting from the inner surfaces near the apex of the ventricles of the heart.

Three types –

Ridges: They are fixed & elevated. They are attached along their total length on one side to form ridges along the interior surface of the ventricle.

Bridges: They have two fixed ends but a free center. It has an important conductive function, containing the right bundle branches.

Papillary muscles: The papillary muscles ‘pull’ on the chordae tendineae to prevent prolapse of the valve leaflets during ventricular systole. They are the following three types:

  1. Anterior It is largest.
  2. Posterior: It is small & irregular.
  3. Septal: It is small.

Fig – trabeculae carneae


It binds the free margins of the cusps of atrio-ventricular orifices with the help of chordae tendineae. The purpose is most likely to prevent suction that would occur with a flat surfaced membrane and thus impair the heart’s ability to pump efficiently. Their structure is vital to their role. Had the inner surface of heart ventricles been flat, suction could happen and this would impair the heart’s ability to pump competently.

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