Papillary muscles

Papillary Muscles

File:Papillary muscles.jpg

Papillary muscles of the human heart, viewed from the base. The anterior, posterior, and septal muscles are labeled.

The Papillary muscles are muscles located in the ventricles of the heart. They attach to the cusps of the atrioventricular valves (also known as the mitral and tricuspid valves) via the chordae tendineae and contract to prevent inversion or prolapse of these valves on systole (or ventricular contraction).

Structure

There are five total papillary muscles in the heart, three in the right ventricle and two in the left. The muscles of the left ventricle are named for their position: the anterolateral papillary muscle and the posteromedial papillary muscle. The three in the right ventricle are the anterior, posterior, and septal papillary muscles.

Function

The papillary muscles play a crucial role in the functioning of the heart. During the contraction of the ventricles, these muscles contract, preventing the atrioventricular valves from prolapsing into the atria, which would cause regurgitation.

Clinical significance

Damage to the papillary muscles can be caused by coronary artery disease, as they are often the last part of the heart to receive blood supply. This can lead to a papillary muscle rupture, which can cause severe mitral regurgitation and is often a complication of a myocardial infarction.

See also

• Heart
• Cardiac muscle
• Mitral valve
• Tricuspid valve