Mitral valve stenosis
Mitral valve stenosis
Mitral valve stenosis — or mitral stenosis — is a condition in which the heart's mitral valve is narrowed (stenotic). This abnormal valve doesn't open properly, blocking blood flow coming into your left ventricle, the main pumping chamber of your heart. Mitral valve stenosis can make you tired and short of breath, among other problems.
The main cause of mitral valve stenosis is an infection called rheumatic fever, which is related to strep infections. Rheumatic fever — now rare in the United States, but still common in developing countries — can scar the mitral valve. Left untreated, mitral valve stenosis can lead to serious heart complications.
You can have mitral valve stenosis and feel fine, or you may have only minimal signs and symptoms for decades. However, mild problems can suddenly get worse. See your doctor if you develop these mitral valve stenosis symptoms:
Mitral valve stenosis symptoms — which may resemble those of other heart or heart valve conditions — may appear or worsen anytime you increase your heart rate, such as during exercise. An episode of rapid heartbeats also may accompany these symptoms. Or they may also be triggered by pregnancy or other stress on your body, such as an infection.
Mitral valve stenosis symptoms usually include those of heart failure. In mitral valve stenosis, pressure that builds up in the heart is then sent back to the lungs, resulting in fluid buildup (congestion) and shortness of breath.
Symptoms of mitral valve stenosis most often appear in your 40s and 50s, but they can occur at any age — even during infancy. Depending on the amount of narrowing, an infant or a child with mitral valve stenosis may have no symptoms, may tire easily or may have shortness of breath with vigorous physical activity.
Mitral valve stenosis may also produce a number of signs that only your doctor will be able to find. These may include:
When to see a doctor
If you've been diagnosed with mitral valve stenosis but haven't had symptoms, talk to your doctor about recommended follow-up.
The heart, the center of your circulatory system, consists of four chambers. The two upper chambers, the atria, receive blood. The two lower chambers, the ventricles, pump blood.
Blood flows through your heart's chambers, aided by four heart valves. These valves open and close to let blood flow in only one direction through your heart. The mitral valve — which lies between the two chambers on the left side of your heart — consists of two triangular flaps of tissue called leaflets.
Heart valves open like a trapdoor. The mitral valve is forced open when blood flows from the left atrium into the left ventricle. When the blood has gone through the valve, the leaflets swing closed to prevent the blood that has just passed into the left ventricle from flowing backward, in the wrong direction.
A defective heart valve is one that fails to either open or close fully. When a valve becomes narrowed and blood flow through it is limited, the condition is called stenosis. Mitral valve stenosis is narrowing of the mitral valve, which obstructs blood flow into the heart's left ventricle.
Causes of mitral valve stenosis include:
Chambers and the valves of the heart
A normal heart has two upper and two lower chambers. The upper chambers, the right and left atria, receive incoming blood. The lower chambers, the more muscular right and left ventricles, pump blood ...
Mitral valve stenosis is less common today than it was several decades ago because the most common cause, rheumatic fever, is rare in the United States. However, rheumatic fever remains a frequent problem in countries where antibiotic use isn't as common.
Risk factors for mitral valve stenosis include a history of rheumatic fever and recurrent strep infections. Radiation treatment involving the chest can result in mitral valve stenosis. Other unusual causes of mitral valve stenosis include medications, such as ergot preparations used for migraines.
Like other heart valve problems, mitral valve stenosis can weaken your heart and decrease how efficiently it pumps blood. Mitral valve stenosis reduces the amount of blood that flows forward through your heart and out to the rest of your body.
Left untreated, mitral valve stenosis can lead to complications such as:
Preparing for your appointment
Your family doctor may be the first to suspect or diagnose mitral valve stenosis. After your initial appointment, your doctor may refer you to a doctor who specializes in the diagnosis and treatment of heart conditions (cardiologist).
Here's some information to help you prepare for your appointment.
What you can do
Questions to ask your doctor at your initial appointment include:
Questions to ask if you are referred to a cardiologist include:
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something.
What to expect from your doctor
What you can do in the meantime
If exercise makes your symptoms worse, avoid exerting yourself physically until you've been seen by your doctor.
Tests and diagnosis
If you develop signs or symptoms of mitral valve stenosis — for example, if you are suddenly breathless with mild exertion — your doctor may ask you to undergo several types of diagnostic tests.
But first your doctor will ask about your medical history and give you a physical examination. As part of your examination, he or she listens carefully to your heart through a stethoscope. Mitral valve stenosis causes an abnormal heart sound, called a heart murmur. A narrowed mitral valve can make a distinct snapping sound followed by a rumbling murmur.
In addition to listening to your heart, your doctor listens to your lungs and the sounds of your breathing. Your doctor is checking for lung congestion — the buildup of fluid in your lungs — that can occur with mitral valve stenosis.
From the initial results, your doctor decides which tests are needed to make a diagnosis. For testing, you may be referred to a cardiologist.
Cardiac tests such as these help your doctor distinguish mitral valve stenosis from other heart conditions, including other problems of the mitral valve. Mitral regurgitation is a condition in which the mitral valve doesn't close tightly. Mitral valve prolapse is a disorder in which the mitral valve sags instead of closing tightly. These conditions may also require treatment.
If you receive a diagnosis of mitral valve stenosis, these tests also help reveal the cause, determine how serious the problem is, and determine whether the mitral valve can be repaired or if replacement may be necessary.
Treatments and drugs
Treatments to prevent permanent damage to your heart from mitral valve stenosis include medications and invasive procedures.
Invasive treatment for mitral valve stenosis isn't always needed right away. If tests reveal that you have mild to moderate mitral valve stenosis and you have no symptoms, there's generally no need for immediate valve repair or replacement. Instead, your doctor will schedule checkups to carefully monitor the valve so that surgery can be done if your condition becomes more severe. Some people never need anything done to the mitral valve because they never develop severe mitral valve stenosis.
For example, your doctor may prescribe:
Repair with balloon valvuloplasty (valvotomy)
Mitral valve surgery
You may continue to be at risk of arrhythmias even after successful surgery for mitral valve stenosis. You may need to take medications to lower that risk or control your heart rate.
Lifestyle and home remedies
To improve your quality of life if you have mitral valve stenosis, your doctor may recommend that you:
If you're a woman with mitral valve stenosis, discuss family planning with your doctor before you become pregnant, because your heart works harder during pregnancy. How a heart with mitral valve stenosis tolerates this extra work depends on the degree of stenosis and how well your heart pumps. If you become pregnant, your cardiologist and obstetrician should evaluate you throughout your pregnancy, labor and delivery, and after delivery.
The best way to prevent mitral valve stenosis is to prevent its most common cause, rheumatic fever. You can do this by making sure you and your children see your doctor when any of you have a sore throat. Untreated strep throat infections can develop into rheumatic fever. Fortunately, strep throat is usually easily treated with antibiotics.
Last Updated: 2011-09-15
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