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Mitral Valve StenosisOverview
What is mitral valve stenosis?Mitral valve stenosis is a heart problem in which the mitral valve doesn't open as wide as it should. It is a lifelong disease. When you first develop it, you most likely have no symptoms and notice no change in your health. Symptoms develop over 10 to 20 years or more. Mitral valve stenosis can lead to heart failure, an infection in the heart (endocarditis), or a fast, slow, or uneven heartbeat (arrhythmia). How does the mitral valve work?Your heart has four chambers and four valves. The valves have flaps, or leaflets. The flaps open and close to keep blood flowing in the proper direction through your heart. The mitral valve connects the heart's upper-left chamber (left atrium) to the lower-left chamber (left ventricle). When the heart pumps, blood forces the flaps open, and blood flows from the left atrium to the left ventricle. Between heartbeats, the flaps close tightly so that blood does not leak backward through the valve. See a picture of the
heart and its chambers, valves, and blood flow See a picture of an
open and closed mitral valve With mitral valve stenosis, the mitral valve becomes stiff or scarred, or the valve flaps become partially joined together. The valve doesn't open as widely as it should. As a result, not as much blood can flow into the left ventricle. More blood stays in the left atrium, and blood may back up into the lungs. See a picture of
mitral valve stenosis What causes mitral valve stenosis?Nearly all cases of mitral valve stenosis are caused by rheumatic fever. This fever results from an untreated strep infection, most often strep throat. But many people who have mitral valve stenosis don't realize they had rheumatic fever. What are the symptoms?Symptoms do not usually develop for 10 to 20 years after stenosis starts, and they may take as long as 40 years to develop.1, 2 After you develop symptoms, they may not become severe for another 3 to 10 years. When symptoms first appear, they usually are mild. You may only have a few symptoms, even if your mitral valve is very narrow. An early symptom is shortness of breath when you are active. This shortness of breath may seem normal to you. Later in the disease, symptoms may include:
Call your doctor if your symptoms get worse or you have new symptoms. How is mitral valve stenosis diagnosed?Mitral valve stenosis may not be diagnosed until you've had the disease for some time. If you don't have symptoms, the first clue might be a heart murmur your doctor hears during a routine checkup. Your doctor will ask you questions about your past health and do a physical exam. If your doctor thinks you might have the disease, he or she may do more tests, which may include:
These tests also help your doctor find what caused the stenosis and how severe it is. How is it treated?Treatment depends on how severe the disease and your symptoms are.
You will likely need regular echocardiograms so your doctor can check for any changes in your mitral valve and heart. Talk to your doctor about your activity and exercise. If your stenosis is mild, you'll probably be able to do your usual activities, get mild exercise, and play some sports. But if your stenosis is moderate or severe, it’s best to avoid intense activity or exercise. Your doctor can help you choose the right type of activity or exercise. Talk to your doctor about how much sodium you can eat. If you have heart failure, you may have to eat less than 2,300 mg of sodium a day. Sodium causes your body to hold extra water. This can make shortness of breath, tiredness, and other symptoms worse. Frequently Asked Questions
CauseVirtually all cases of mitral valve stenosis are caused by rheumatic fever, which can follow an untreated strep throat infection. But many people who have mitral valve stenosis don't realize they had rheumatic fever. In recent decades, cases of rheumatic fever have decreased considerably in Canada, the United States, and western Europe. But many people throughout the world still get rheumatic fever. This may include immigrants from regions where rheumatic fever is more common. Other less common causes of mitral valve stenosis include:
SymptomsAlthough mitral valve stenosis is a lifelong disease, symptoms usually take 10 to 20 years to develop and can take as long as 40 years.1, 2 Early symptoms are often mild and hard to distinguish from other forms of heart disease. In the later stages of mitral valve stenosis, the left atrium may become damaged, causing more noticeable symptoms.
You may not have any symptoms until an aggravating event—such as exercise, stress, pregnancy, infection, or an irregular heartbeat—occurs. Or you may have only a few symptoms, regardless of how far the stenosis has progressed. It is important that your doctor monitor your condition for physical changes in your heart and lungs that you might not be aware of. Additional symptoms of mitral valve stenosis are related to developing heart failure and include an irregular heart rhythm (most often due to atrial fibrillation). Other less common symptoms include:
Because these symptoms could be caused by various heart and lung problems, it may be difficult at first to connect them to mitral valve stenosis. Symptoms may not become severe for another 3 to 10 years after they first become noticeable. It is often the development of one or more complications of mitral valve stenosis that leads to its diagnosis. What Increases Your RiskThe three main risk factors for mitral valve stenosis are:
Less commonly, diabetes and Marfan's syndrome can lead to mitral valve stenosis, causing calcification, or hardening, of the mitral valve's base. This limits the valve's flexibility and slows its rhythmic movements. Any condition that scars the valves, such as endocarditis, may lead to mitral valve stenosis. But, these conditions usually raise the chance of getting mitral valve regurgitation rather than stenosis. Little can be done to prevent mitral valve stenosis. Similarly, after you develop the condition, you cannot prevent the start of symptoms or predict how quickly symptoms will develop. Fortunately, mitral valve stenosis can be treated, and few people die from it. When to Call a DoctorCall 911 or other emergency services immediately if you have:
Call a doctor immediately if you have:
Watchful waitingEpisodes of chest pain or palpitations may come and go and may not be associated with other serious heart disease. But contact your doctor when:
Who to seeHealth professionals who can evaluate symptoms and order further tests as needed include: These health professionals can provide management and monitoring. If you have severe mitral valve stenosis, you should see a cardiologist. A cardiovascular surgeon may perform surgical repair of heart valves. Exams and TestsMitral valve stenosis is a "quiet" condition—it often has no symptoms in its early stages and may not be diagnosed until you've had the disease for some time. If you are not having symptoms, such as shortness of breath or pounding of the heart, the first indication of mitral valve stenosis could be a suspicious heart murmur that your doctor hears during a routine checkup. Medical history and physical examA review of your medical history and a physical exam can predict whether you have mitral valve stenosis and help determine future treatment. Your doctor will ask about your lifestyle, activity level, and any conditions that you or any of your immediate family members have had. Your doctor will want to know about any symptoms you are having and if you have ever had:
During the physical exam, the doctor will take your blood pressure, check your pulses, listen to your heart (possibly while you are lying on your left side) and lungs, and look for signs of fluid buildup (edema). Findings that may indicate a problem with your heart or heart valves include:
EchocardiogramAn echocardiogram is used to determine whether mitral valve stenosis is present and to estimate its severity. Echocardiography uses high-pitched sound waves to produce an image of the heart. Specifically, an echocardiogram can show structural problems of the heart that may affect the mitral valve. Transesophageal echocardiography is often used in people when evaluating the heart through a thick chest wall is difficult. For this procedure, a device that uses ultrasound waves to produce an image of the heart is inserted through the mouth and down the throat into the esophagus. This test is often used—at the end of a mitral valve surgery, before the surgeon closes the incision—to see whether the valve is working properly. Echocardiography should be considered if the doctor suspects mitral valve stenosis, whether or not symptoms are present, or if you have associated conditions such as heart failure or atrial fibrillation. Your doctor can use an echocardiogram to:
You will likely have regular echocardiograms so your doctor can keep track of any changes in your condition. How often you get an echocardiogram depends on the severity of your mitral valve stenosis. Your doctor may recommend an echocardiogram every year if you have severe stenosis, every 1 to 2 years if you have moderate stenosis, or every 3 to 5 years if you have mild stenosis.2 An echocardiogram can also help determine whether other heart conditions are also present, such as mitral valve regurgitation or aortic valve regurgitation. ElectrocardiogramElectrocardiogram is used to measure the electrical activity in the heart by attaching small metal discs called electrodes to the chest, arms, and legs. The electrodes are also connected to a machine that translates the electrical activity into line tracings on paper. These tracings are often analyzed by the machine and then carefully reviewed by a doctor for abnormalities. This test is usually part of the standard evaluation of a person with symptoms of mitral valve stenosis. An electrocardiogram (EKG or ECG) can:
Chest X-rayA chest X-ray may show evidence of mitral valve stenosis, such as enlargement of the upper left heart chamber (left atrium), enlargement of the pulmonary arteries, and too much blood and backup of fluid in the lungs (pulmonary edema). Calcium deposits on the heart valves occasionally may be seen on a chest X-ray, especially if the buildup is severe. An EKG and chest X-ray find evidence of mitral valve stenosis only if it has caused other problems. These include enlargement of the heart (dilation), a thickened heart muscle (hypertrophy), an abnormal left atrium, an irregular heartbeat (arrhythmia), or an insufficient blood flow to the heart (ischemia). Cardiac catheterizationCardiac catheterization is usually done before any surgery for mitral valve
stenosis to evaluate your heart, the degree of stenosis, and the heart
(coronary) arteries. During a cardiac catheterization, the pressure in the
heart chamber above the mitral valve (left atrium This test may be needed when results of echocardiography are inconclusive or inconsistent with your symptoms. It can also identify other heart conditions that may cause symptoms similar to mitral valve stenosis. For example, it can evaluate the coronary arteries and check for coronary artery disease. Knowing the condition of the coronary arteries may affect later treatment decisions for mitral valve stenosis. Treatment OverviewKey pointsTreatment of mitral valve stenosis depends on the severity of your symptoms, which can take 10 to 40 years to develop. If you haven't yet developed symptoms or you have mild, stable symptoms, your doctor may only monitor your condition with periodic echocardiograms. As the valve narrows, symptoms will develop or get worse. Repair or replacement of the valve will be necessary to prevent complications such as heart failure. As you review your treatment options, consider the following:
Initial treatmentMitral valve stenosis develops slowly. As the valve narrows, the heart initially
compensates by pumping harder. Eventually pressure builds in the upper left
side of your heart (left atrium Symptoms most commonly develop when unusual stress places an extra burden on your heart. For example, hard exercise can bring on symptoms. Symptoms in women may develop during pregnancy because of the increased demands that pregnancy makes on the heart. Ongoing treatmentYour doctor may prescribe medicines to manage the symptoms of mitral valve stenosis that you've developed, such as shortness of breath, and to prevent and treat complications that may develop. These medicines may include:
Treatment if the condition gets worseAs your mitral valve stenosis gets worse, there will come a time when your doctor will advise repairing or replacing your mitral valve. Mitral valve repair may be done in one of two ways:
Mitral valve replacement surgery is also an open-heart procedure. The damaged heart valve is removed and replaced with a new valve. It is generally the last choice in mitral valve stenosis treatment because an artificial mitral valve cannot work as well as a normal mitral valve. Your doctor will likely recommend valve replacement if the valve has deteriorated to the point that repair is not an option or if the anatomy of the valve has been changed by one or more repair procedures and can no longer be repaired. See a picture of
mitral valve replacement surgery Ongoing ConcernsAfter you develop symptoms of mitral valve stenosis, it usually takes about 3 to 10 years before they become disabling. As long as your symptoms are mild or stable, your doctor may be able to keep them under control with medicines. As your symptoms increase and your valve width decreases, surgery to repair or replace the valve will become necessary. ComplicationsAlthough mitral valve stenosis can be an easy condition to overlook in its mild form, as it progresses it often has serious complications. The most common complications are an irregular heartbeat (arrhythmia), heart failure, and an infection in the heart (endocarditis). All of these are serious medical conditions that require treatment, and you and your doctor should discuss the most appropriate ways to prevent and treat them. For more information, see the topics Heart Failure, Atrial Fibrillation, and Endocarditis.
Living With Mitral Valve StenosisSerious heart damage can result from long-term mitral valve stenosis. If you have been diagnosed with the condition, it is important to talk to your doctor about how often you should be examined. SymptomsBe especially alert for new symptoms or symptoms getting worse, such as:
Call your doctor if your symptoms get worse or if new symptoms start. ExercisePeople who have severe mitral valve stenosis may need to be cautious about their level of physical activity. If you don't exercise, talk to your doctor before you start. You may be able to do certain types of exercise that don't put undue strain on your heart. If you don't have symptoms, discuss exercise with your doctor. If your stenosis is mild, normal activities, mild exercise, and in some cases competitive sports may be allowed. But if your stenosis is moderate or severe and you have symptoms, you should avoid strenuous activity. You may be able to do low-level activities to help keep your heart healthy. If you have a physically demanding job, you may need to change careers. Talk with your doctor to determine a safe level of activity. DietDepending on how bad your condition and symptoms are, your doctor may advise you to limit salt in your diet to less than 2,300 mg a day. If you consume too much sodium, it will cause your body to retain excess fluid. Excess fluid in the body will cause swelling, breathing difficulties, fatigue, and other unpleasant side effects. Salt restriction usually includes avoiding potato chips, pretzels, salted nuts, processed meats and cheeses, pizza, canned soups, canned vegetables, olives, fast foods, and frozen dinners (unless the label clearly states the product is low-sodium). Add more fresh fruit and vegetables to your diet to replace foods high in sodium. When you are grocery shopping, check labels carefully for hidden sodium. AntibioticsIf you have an artificial valve, you may need to take antibiotics before you have certain dental or surgical procedures. The antibiotics help prevent an infection in your heart called endocarditis.
MedicationsMedicines are often used to relieve the symptoms and prevent complications of mitral valve stenosis. Usually they are also prescribed after you have surgery to repair or replace your mitral valve. Medicines to treat symptoms include:
Medicines are used to treat complications. Complications may include:
What to think aboutTalk with your doctor about the need for medicine. If you have used the now-banned, weight-loss medication fen-phen, there may be specific concerns about your heart valves. SurgeryIf medicines are not effective in controlling your symptoms of mitral valve stenosis or if your doctor determines that you need more aggressive treatment, you may need surgery to repair or replace your mitral valve. While valve surgery is common and usually successful, a degree of risk is associated with this invasive procedure. There are generally three options: a balloon valvotomy, a closed (or open) commissurotomy surgery, or valve replacement surgery. Valve repair (balloon valvotomy)Balloon valvotomy (percutaneous mitral balloon valvotomy) is the method of choice for treating mitral valve stenosis in select patients. A thin flexible tube (catheter) is inserted through an artery in the groin or arm and threaded into the heart. When the tube reaches the narrowed mitral valve, a balloon located on the tip of the catheter is quickly inflated. The balloon, pressing against the narrowed mitral valve leaflets, separates and stretches the valve opening and allows more blood to flow through the heart. This procedure does not require open-heart surgery, so recovery is easier. A balloon valvotomy is usually recommended if you have symptoms, moderate to severe stenosis, and most of your mitral valve is a normal shape.2 Your doctor will measure your pressure gradient and valve size to determine how bad the stenosis is. A normal mitral valve has an opening between 4 cm2 and 5 cm2. A balloon valvotomy may also be used to treat people with mitral valve stenosis who do not yet have symptoms (asymptomatic) if they have:2
Your doctor may recommend a balloon valvotomy if you are planning to have another surgery (not on your heart), if you are pregnant, or if you are planning a pregnancy. People with signs of blood clots in the left atrium, widespread calcification of the mitral valve structures, or moderate to severe mitral valve regurgitation are not considered good candidates for a balloon valvotomy.2 The mitral valve may narrow again (restenosis) after 10 to 20 years. Valve surgeryDepending on the amount of damage to your mitral valve, your doctor may recommend surgery to repair or replace your mitral valve. If the valve is damaged beyond repair, it will need to be replaced. Mitral valve surgery may be done as an open-heart surgery, or a minimally invasive surgery. During open-heart surgery, your heartbeat is stopped, and you are placed on a heart-lung machine to deliver blood to your body. The heart-lung machine temporarily serves in place of your heart and lungs by mixing oxygen with the blood, removing carbon dioxide from the blood, and pumping the blood throughout your body. During minimally invasive surgery, your doctor makes a smaller incision than the incision made in open-heart surgery. You may still be placed on a heart-lung machine. Valve repair or replacement is similar for minimally invasive surgery and open-heart surgery. Valve repair In open commissurotomy, a surgeon removes calcium deposits and other scar tissue from the mitral valve leaflets, which opens the valve. This procedure is used for people who have severe narrowing of the valve and are not good candidates for balloon valvotomy. Valve replacement The damaged heart valve is removed and replaced with a new valve. This is generally done when your mitral valve is damaged beyond repair. With improved technology, mitral valve replacement is an important surgical option. Some doctors believe that replacement mitral valves are now more durable. In addition, more of the original mitral valve and its support structure (such as the chordae tendineae) are preserved during valve replacement. The long-term results of surgery are generally better when more of the original mitral valve structure is preserved. Replacement heart valvesThere are two types of replacement valves:
Most people who have mitral valve replacement surgery will receive a mechanical heart valve. Even if a bioprosthetic tissue valve is used, you will need to take anticoagulants if you also have other heart conditions such as abnormal heartbeat (arrhythmia) or a dilated left atrium, because both of these conditions are risk factors for stroke. Other Places To Get HelpOrganizations
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