The heart has 4 chambers. The two smaller chambers on top are called atria and the two larger chambers at the bottom are called ventricles. Mitral valve is the door present between the left atrium and left ventricle. This door normally closes when the left ventricle is trying to pump out the blood to the body, which is its normal function. Mitral regurgitation occurs when this door doesn't close properly, thus resulting in the blood leaking from the left ventricle back into the smaller top chamber i.e. the left atrium.
If the leakage of blood is in significant amount, you can expect to have:
1- Shortness of breath
3- Fluid collection in your body presenting as swelling of legs
The clinical symptoms, as described above, will likely raise the suspicion of a valvular problem, to confirm which some workup will be done. It includes:
1- Chest X-ray: It will show fluid in lungs or an enlarged heart in this condition.
2- EKG: It is a quick test to check the electrical activity of the heart. It can give information regarding any previous heart attacks or heart rhythm problems which may have resulted in this valvular condition.
3- Echocardiography: It is an ultrasound of the heart, and gives information about the normal functioning of the heart valves. It is the best test to diagnose this condition.
If your symptoms are very mild and the leakage of blood is very small, then your physician will likely just monitor you with regular follow-ups. If the valve leakage is quite large and your symptoms are getting worse, then your doctor will prescribe you some medications to alleviate the symptoms. In severe situations, surgery may be required to either repair or replace the damaged valve.