The mitral valve controls flow from the left atrium into the left ventricle. Named after a bishop's mitre, it has two leaflets, a larger anterior and a longer-based posterior, held by chordae tendineae to two papillary muscles. It is the only heart valve with two leaflets.
| Location | Left atrioventricular orifice, behind the left half of the sternum at about the fourth costal cartilage. Its sounds are best heard at the cardiac apex. |
|---|---|
| Parts |
|
Opens in diastole to allow left ventricular filling and closes at the start of systole to stop blood being forced back into the left atrium and lungs. Its closure is the main component of the first heart sound.
Mitral valve prolapse is common and usually benign, but some cases progress to severe regurgitation that needs repair. Rheumatic heart disease, still common worldwide, mainly causes mitral stenosis. Mitral regurgitation can appear suddenly after papillary muscle or chordal rupture and needs emergency care.
Narrowing of the valve opening, mostly from rheumatic fever. Pressure backs up into the left atrium and lungs, causing breathlessness and atrial fibrillation.
Leakage of blood back into the left atrium during systole, from prolapse, ruptured chordae, infarction or a dilated ventricle. Severe cases cause heart failure.
Billowing of one or both leaflets back into the left atrium during systole, often producing a click and late murmur. Most people have no symptoms.
This website uses cookies to enhance your experience. Some are essential for site functionality, while others help us analyze and improve your usage experience. Please review your options and make your choice.
If you are under 16 years old, please ensure that you have received consent from your parent or guardian for any non-essential cookies.
Your privacy is important to us. You can adjust your cookie settings at any time. For more information about how we use data, please read our privacy policy. You may change your preferences at any time by clicking on the settings button below.
Note that if you choose to disable some types of cookies, it may impact your experience of the site and the services we are able to offer.
Some required resources have been blocked, which can affect third-party services and may cause the site to not function properly.
This website uses cookies to enhance your browsing experience and ensure the site functions properly. By continuing to use this site, you acknowledge and accept our use of cookies.
