Blood Supply of The Papillary Muscles.
The papillary muscles attach the mitral valve (the valve between the left atrium and the left ventricle) and the tricuspid valve (the valve between the right atrium and the right ventricle) to the wall of the heart. If the papillary muscles are not functioning properly, the mitral valve may leak during contraction of the left ventricle. This causes some of the blood to travel "in reverse", from the left ventricle to the left atrium, instead of forward to the aorta and the rest of the body. This leaking of blood to the left atrium is known as mitral regurgitation. Similarly, the leaking of blood from the right ventricle through the tricuspid valve and into the right atrium can also occur, and this is described as tricuspid insufficiency or tricuspid regurgitation.
The anterolateral papillary muscle more frequently receives two blood supplies: left anterior descending (LAD) artery and the left circumflex artery (LCX). It is therefore more frequently resistant to coronary ischemia (insufficiency of oxygen-rich blood). On the other hand, the posteromedial papillary muscle is usually supplied only by the PDA. This makes the posteromedial papillary muscle significantly more susceptible to ischemia. The clinical significance of this is that a myocardial infarction involving the PDA is more likely to cause mitral regurgitation.
Read more about this topic: Coronary Circulation
Famous quotes containing the words blood, supply and/or muscles:
“This nation is founded on blood like a city on swamps
yet its dream has been beautiful and sometimes just
that now grows brutal and heavy as a burned out star.”
—Marge Piercy (b. 1936)
“There never has been a time in our history when work was so abundant or when wages were as high, whether measured by the currency in which they are paid or by their power to supply the necessaries and comforts of life.”
—Benjamin Harrison (1833–1901)
“What is this beast, she thought,
with muscles on his arms
like a bag of snakes?
What is this moss on his legs?
What prickly plant grows on his cheeks?
What is this voice as deep as a dog?”
—Anne Sexton (1928–1974)