Mitral Valve Disease
What is the mitral valve?
Your mitral valve is located between the left atrium and left ventricle of your heart. It regulates the flow of blood from your lungs into the left ventricle, the main pumping chamber.
Oxygen-rich blood comes from your lungs and fills the left atrium. It then passes through your mitral valve into the left ventricle, where it is pumped out to the rest of the body. Your mitral valve closes to keep blood from leaking backward when the ventricle contracts.
The valve itself consists of two flaps or leaflets. Small cord-like tendons connect the mitral valve to the heart muscle.
What is mitral stenosis?
Mitral stenosis occurs when your mitral valve is narrowed and does not open fully. The tight valve prevents blood from flowing into the left ventricle properly. Because of this, your heart has to work harder to pump blood through the smaller valve opening. Over time this can cause pressure and fluid to build up in your lungs.
What are the common causes for mitral stenosis?
Mitral stenosis is most commonly caused by rheumatic fever. Rheumatic fever results from an untreated strep infection, like strep throat. This can damage your mitral valve by causing the leaflets to thicken and scar. Rheumatic fever is less common today due to increased availability of antibiotic treatments.
Less commonly, mitral stenosis can be caused by a congenital heart defect.
What are the symptoms of mitral stenosis?
Symptoms do not typically develop for 10 to 20 years after the disease starts. They are usually mild at first and may not become severe for many years:
- Shortness of breath during activity which develops into shortness of breath with minimal activity or when resting or lying down
- Extreme fatigue or tiredness
- Rapid, pounding heartbeat
What is mitral regurgitation (MR)?
Mitral regurgitation or insufficiency occurs when your mitral valve does not close properly. Blood leaks backward into the left atrium and lungs, forcing your heart has to work harder to pump blood out to the body.
What are common causes for mitral regurgitation?
Most often, mitral regurgitation develops slowly over time. As you get older, your valve weakens and no longer closes tightly. Mitral regurgitation is commonly caused by mitral valve prolapse. This occurs when one of the leaflets slips in the wrong direction, allowing blood to leak.
Mitral regurgitation can also be caused by a number of other heart conditions including:
- Congenital heart disease
- Heart failure
- Rheumatic fever
- Bacterial infections called endocarditis
- Calcium and fat deposits on the valve
- Damage due to a heart attack
What are the symptoms of mitral regurgitation?
Symptoms of mitral regurgitation may take decades to surface. If you have mild or moderate disease, you may never have symptoms. Symptoms are a result of weakened heart muscle because of your leaky valve. Symptoms include:
- Shortness of breath during activity that later develops into shortness of breath with minimal activity or when resting or lying down
- Extreme fatigue and weakness
- Excess fluid in your legs and feet (edema)
What are the symptoms of mitral prolapse?
- Chest pain
- Feeling your heart beating fast or hard
- Fainting or feeling dizzy
How is mitral valve disease diagnosed and evaluated?
Valve disease may be detected by your doctor during a routine medical exam. A heart murmur is the sound of blood flowing across an abnormal heart valve and may be the first clinical sign of valve disease, if you have no symptoms. Your doctor may order an echocardiogram (an external ultrasound of your heart) to look at your heart valves.
Echocardiogram: An echocardiogram or "echo" uses sound waves to create a picture of your heart. It shows the different structures of the heart and can show any abnormalities in your valves. There are two kinds of echocardiograms. Your doctors will determine which test is needed to get the best view of your heart valves.
- Transthoracic echocardiograms (TTE): A TTE is done using an ultrasound probe held against the chest and is noninvasive.
- Transesophageal echocardiograms (TEE): A TEE is done by passing an ultrasound probe down the esophagus to get a close up view of your heart. This test is more invasive.
What are the treatment options for mitral valve disease?
Treatment includes both medical and surgical options. Surgical treatments range from less invasive, using catheter-based procedures, to more invasive requiring open heart surgery. Your heart doctors will discuss which treatment options are appropriate for your valve disease.
- Medical management: Depending on the severity, treatment with medications may be successful in managing your valve disease. Medications can be helpful in treating your symptoms. However, they will not prevent or reverse the disease. It is important to keep close follow up with your heart doctor. This includes regular appointments, living a healthy lifestyle, and taking the medications to help your heart. You will likely have routine echocardiograms to monitor the progression of the disease.
- Valvuloplasty: This procedure uses a balloon catheter to stretch the opening of your valve allowing more blood to flow through. This procedure provides temporary relief of symptoms.
- Mitraclip: This procedure may be an option if you have mitral regurgitation and do not want open heart surgery. It allows the diseased heart valve to be replaced using a catheter and is less invasive than surgical mitral valve replacement. Candidacy for this procedure is determined through a series of screening tests and may not be appropriate for all patients.
Surgical Treatment: Mitral valve surgery is a surgical procedure where your mitral valve is either repaired or replaced by a properly functioning valve. Mitral valve repair is preferred over replacement whenever possible. At UW Health, our surgeons are able to repair mitral valves more often than not.