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:
“The grand principles of virtue and honor, however they may be distorted by arbitrary codes, are the same the world over: and where these principles are concerned, the right or wrong of any action appears the same to the uncultivated as to the enlightened mind.”
—Herman Melville (18191891)
“The highest proof of civility is that the whole public action of the State is directed on securing the greatest good of the greatest number.”
—Ralph Waldo Emerson (18031882)
“The moment we choose to love we begin to move against domination, against oppression. The moment we choose to love we begin to move towards freedom, to act in ways that liberate ourselves and others. That action is the testimony of love as the practice of freedom.”
—bell hooks (b. c. 1955)