QS Study

The conical muscular projections from the ventricular walls arc called papillary muscle. They are thick bands and ridges of endocardial-lined myocardium that project into the lumen of the cardiac ventricles. It refers to a tiny muscle inside the heart that serves as an anchor for the cardiac valves.

Number

Usually three in right ventricle & two in the left ventricle –

In right ventricle:

  • Anterior papillary muscle – the muscle attaches to the chordae tendineae of the anterior and posterior cusps.
  • Posterior papillary muscle – the muscle attaches to the chordae tendineae of the posterior and septal cusps
  • Septal papillary muscle – the attaches to the chordae tendineae of the anterior and septal cusps.

In left ventricle:

  • Anterior papillary muscle – attaches to the chordae tendineae of the anterior and posterior cusps.
  • Posterior papillary muscle – attaches to the chordae tendineae of the anterior and posterior cusps.

Fig: Papillary Muscle

Situation

Each papillary muscle has two ends. One end is attached to the ventricular wall and another end is connected with the cusp by chorda tendineae.

Functions10

They maintain the position of the cusps with the help of chordae tendineae during ventricular systole. They essentially represent dominant ventricular trabeculae which attach to the cusps of the atrioventricular valves via the chordae tendineae.

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