Mitral Valve Function and Disorders
The mitral valve is located between the heart's left atrium and left ventricle. The valve itself consists of two flaps (or leaflets) surrounded by a fibrous ring (the annulus). Muscles and tendons lie underneath the valve. All of the components must work together to ensure the valve functions normally.
Oxygen-rich blood flows from the lungs into the left atrium. It then passes through the open mitral valve into the left ventricle, which is the heart's main pumping chamber. When the left ventricle contracts, the mitral valve closes. This forces the blood to flow from the left ventricle to the aorta, and out to the body.
Mitral Valve Regurgitation
If the valve does not close properly, blood can leak backward into the left atrium and lungs. This is called mitral valve regurgitation. Mitral valve regurgitation results from the abnormal function of any of the components of the valve, such as:
- Degenerative mitral valve disease
- Congenital defects
- Muscle weakness due to previous heart attacks
Mitral Valve Stenosis
A less common valve disorder is mitral valve stenosis. This is when the mitral valve narrows and does not open properly. The tight valve prevents blood from flowing into the left ventricle. Mitral valve stenosis is found in individuals who have had rheumatic heart disease.
Left untreated, mitral valve disorders can cause shortness of breath, weakening of the heart muscle, congestive heart failure, and death.