Papillary Muscle - Action

Action

There are five total papillary muscles in the heart, three in the right ventricle and two in the left. The anterior, posterior, and septal papillary muscles of the right ventricle each attach via chordae tendineae to the tricuspid valve. The anterior and posterior papillary muscles of the left ventricle attach via chordae tendineae to the mitral valve.

The papillary muscles of both the right and the left ventricles begin to contract shortly before ventricular systole and maintain tension throughout. This prevents regurgitation--backward flow of ventricular blood into the atrial cavities--by bracing the atrioventricular valves against prolapse--being forced back into the atria by the high pressure in the ventricles.

Read more about this topic:  Papillary Muscle

Famous quotes containing the word action:

    To play is nothing but the imitative substitution of a pleasurable, superfluous and voluntary action for a serious, necessary, imperative and difficult one. At the cradle of play as well as of artistic activity there stood leisure, tedium entailed by increased spiritual mobility, a horror vacui, the need of letting forms no longer imprisoned move freely, of filling empty time with sequences of notes, empty space with sequences of form.
    Max J. Friedländer (1867–1958)

    Let those who go home tell the same story of you:
    Of action with a common purpose, action
    None the less fruitful if neither you nor we
    Know, until the moment after death
    What is the fruit of action.
    —T.S. (Thomas Stearns)

    Wherever you see a man who gives someone else’s corruption, someone else’s prejudice as a reason for not taking action himself, you see a cog in The Machine that governs us.
    John Jay Chapman (1862–1933)