Papillary muscle
A papillary muscle ( Musculus papillaris ) is a wart-shaped protrusion of the heart muscle into the heart's interior, which is connected by tendon threads ( Chordae tendineae ) to two of the leaflets of a leaflet valve between the atrium (atrium) and the heart chamber (ventricle) ( mitral and tricuspid valve ).
The tendon threads are tightened by the contraction of the papillary muscles. However, this does not lead to the opening or closing of the valves, which are only moved passively due to the pressure differences between atrium and ventricle, but merely prevents the valves from breaking through back into the atria.
There are three papillary muscles in the right ventricle and only two in the left.
A papillary muscle tear can occur as part of a myocardial infarction . This occurs more frequently on the left rear muscle and can thus lead to acute mitral valve insufficiency or mitral valve prolapse and thus possibly acute left heart failure and, as a result, possibly to cardiogenic shock . If the right papillary muscles are affected, tricuspid regurgitation occurs and, as a result, right heart failure.
In the EKG , the repolarization of the papillary muscles results in the so-called U-wave. However, this is not physiologically visible and is particularly evident in hypokalemia .
Individual evidence
- ^ Herbert Lippert: Textbook anatomy. 7th expanded edition. Elsevier - Urban and Fischer, Munich 2006, ISBN 3-437-42362-2 , p. 231.