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heart valve disease





Contents
  • What causes heart valve disease?
  • Who is at risk?
  • Signs and symptoms
  • Diagnosis
  • Treatment
  • Prevention
  • Living with heart valve disease
  • Heart valve disease is a condition in which one or more of the heart valves don't work properly. The heart has four valves: the tricuspid, pulmonary, mitral, and aortic valves. These valves have tissue flaps that open and close with each heartbeat. The flaps make sure blood flows in the right direction through the heart's four chambers and to the rest of your body.

    Birth defects, age-related changes, infections, or other conditions can cause one or more of the heart valves to not open fully or to let blood leak back into the heart chambers. This can make the heart work harder and affect its ability to pump blood.





    Overview

    How the heart valves work

    At the start of each heartbeat, blood returning from the body and the lungs fills the heart's two upper chambers. The mitral and tricuspid valves are located at the bottom of these chambers. As the blood builds up in the upper chambers, these valves open to allow blood to flow into the lower chambers of your heart.

    After a brief delay, as the lower chambers begin to contract, the mitral and tricuspid valves shut tightly. This stops blood from flowing backward.

    human heart


    As the lower chambers contract, they pump blood through the pulmonary and aortic valves. The pulmonary valve opens to allow blood to flow from the right lower chamber into the pulmonary artery. This artery carries blood to the lungs to get oxygen.

    At the same time, the aortic valve opens to allow blood to flow from the left lower chamber into the aorta. This aorta carries oxygen-rich blood to the body. As the contraction ends, the pulmonary and aortic valves shut tightly. This stops blood from flowing backward into the lower chambers.


    Heart valve problems

    Heart valves can have three basic kinds of problems:
    • Regurgitation, or backflow, occurs when a valve doesn't close tightly. Blood leaks back into the chamber rather than flowing forward through the heart or into an artery. In the United States, backflow is most often due to prolapse. "Prolapse" is when the flaps of the valve flop or bulge back into an upper heart chamber during a heartbeat. Prolapse mainly affects the mitral valve, but it can affect the other valves as well.

    • Stenosis occurs when the flaps of a valve thicken, stiffen, or fuse together. This prevents the heart valve from fully opening, and not enough blood flows through the valve. Some valves can have both stenosis and backflow problems.

    • Atresia occurs when a heart valve lacks an opening for blood to pass through.
    You can be born with heart valve disease or you can acquire it later in life. Heart valve disease that develops before birth is called a congenital valve disease. Congenital heart valve disease can occur alone or with other congenital heart defects.

    Congenital heart valve disease usually involves pulmonary or aortic valves that don't form properly. These valves may not have enough tissue flaps, they may be the wrong size or shape, or they may lack an opening through which blood can flow properly.

    Acquired heart valve disease usually involves the aortic or mitral valves. Although the valve is normal at first, disease can cause problems to develop over time.

    Both congenital and acquired heart valve disease can cause stenosis or backflow.


    Outlook

    Many people have heart valve defects or disease but don't have symptoms. For some people, the condition will stay largely the same over their lifetime and not cause any problems.

    For other people, the condition will worsen slowly over time until symptoms develop. If not treated, advanced heart valve disease can cause heart failure, stroke, blood clots, or sudden death due to sudden cardiac arrest.

    Currently, no medicines can cure heart valve disease. However, lifestyle changes and medicines can relieve many of the symptoms and problems linked to heart valve disease. They also can lower your risk of developing a life-threatening condition, such as stroke or sudden cardiac arrest. Eventually, you may need to have your faulty heart valve repaired or replaced.

    Some types of congenital heart valve disease are so severe that the valve is repaired or replaced during infancy or childhood or even before birth. Other types may not cause problems until you're middle-aged or older, if at all.


    What causes heart valve disease?

    Heart conditions and other disorders, age-related changes, rheumatic fever, and infections can cause acquired heart valve disease. These factors change the shape or flexibility of once-normal valves.

    The cause of congenital heart valve defects isn't known. These defects occur before birth as the heart is forming. Congenital heart valve defects can occur alone or with other types of congenital heart defects.


    Heart conditions and other disorders

    Heart valves can be stretched and distorted by:
    • Damage and scar tissue due to a heart attack or injury to the heart.
    • Advanced high blood pressure and heart failure. These conditions can enlarge the heart or the main arteries.
    • Narrowing of the aorta due to the buildup of a fatty material called plaque inside the artery. The aorta is the main artery that carries oxygen-rich blood to the body. The buildup of plaque inside an artery is called atherosclerosis.

    Age-related changes

    Men older than 65 and women older than 75 are prone to developing calcium and other deposits on their heart valves. These deposits stiffen and thicken the valve flaps and limit blood flow (stenosis).

    The aortic valve is especially prone to this problem. The deposits resemble those seen in the narrowed and hardened blood vessels of people who have atherosclerosis. Some of the same processes may cause both atherosclerosis and heart valve disease.


    Rheumatic fever

    Some people have heart valve disease due to untreated strep throat or other infections with strep bacteria, which progress to rheumatic fever.

    When the body tries to fight the strep infection, one or more heart valves may be damaged or scarred in the process. The aortic and mitral valves are most often affected. Symptoms due to heart valve damage often don't appear until many years after recovery from rheumatic fever.

    Today, most people with strep infections are treated with antibiotics before rheumatic fever develops. It's very important to take the entire amount of antibiotics your doctor prescribes for strep throat, even if you feel better.

    Heart valve disease due to rheumatic fever mainly affects older people who had strep infections before antibiotics were available. It also affects people from developing countries, where rheumatic fever is more common.


    Infections

    Common germs that enter through the bloodstream and get carried to the heart can sometimes infect the inner surface of the heart, including the heart valves. This rare, but sometimes life-threatening infection is called endocarditis.

    The germs can enter the bloodstream through needles, syringes, or other medical devices and through breaks in the skin or gums. Usually the body's defenses fight off the germs and no infection occurs. Sometimes these defenses fail, which leads to endocarditis.

    Endocarditis can develop in people who already have abnormal blood flow through a heart valve due to congenital or acquired heart valve disease. The abnormal blood flow causes blood clots to form on the surface of the valve. The blood clots make it easier for germs to attach to and infect the valve.

    Endocarditis can worsen existing heart valve disease.


    Other conditions and factors linked to heart valve disease

    A number of other conditions and factors are sometimes linked to heart valve disease. However, it's often unknown how these conditions actually cause heart valve disease.
    • Systemic lupus erythmatosis (SLE). SLE and other immune diseases can affect the aortic and mitral valves.

    • Carcinoid syndrome. Tumors in the digestive tract that spread to the liver or lymph nodes can affect the tricuspid and pulmonary valves.

    • Metabolic disorders. Relatively uncommon diseases, such as Fabry disease and hyperlipidemia, can affect the heart valves.

    • Diet medicines. The use of fenfluramine and phentermine ("fen-phen") has sometimes been linked to heart valve problems. These problems typically stabilize or improve after the medicine is stopped.

    • Radiation therapy. Radiation therapy to the chest area can cause heart valve disease. This therapy is used to treat cancer. Heart valve disease due to radiation therapy may not cause symptoms for as many as 20 years after the therapy ends.

    • Marfan syndrome. Congenital disorders, such as Marfan syndrome, and other connective tissue disorders mainly affect the structure of the body's main arteries. However, these conditions also can also affect the heart valves.

    Who is at risk for heart valve disease?


    Populations affected

    Older people are more likely to develop heart valve disease. It's estimated that 1 in 8 people age 75 or older have at least moderate heart valve disease.

    People who have a history of endocarditis, rheumatic fever, heart attack, or heart failure – or previous heart valve disease – are more likely to develop heart valve disease.

    About 1 to 2 percent of people are born with an aortic valve that has two flaps instead of three. Sometimes an aortic valve may have three flaps, but two flaps are fused together and act as one flap. This is called a bicuspid or bicommissural aortic valve. People who have this congenital condition are more likely to develop aortic heart valve disease.


    Major risk factors

    The major risk factors for acquired heart valve disease are:
    • Age

    • Heart disease risk factors, such as high blood cholesterol levels, high blood pressure, smoking, insulin resistance, diabetes, overweight or obesity, lack of physical activity, and a family history of early heart disease

    • Risk factors for endocarditis, such as intravenous drug use

    What are the signs and symptoms of heart valve disease?


    Major signs and symptoms

    The main sign of heart valve disease is an unusual heart sound called a heart murmur. Your doctor can hear a heart murmur with a stethoscope.

    However, many people have heart murmurs without having heart valve disease or any other heart problems. Others may have heart murmurs due to heart valve disease, but have no other signs or symptoms.

    Heart valve disease often worsens over time, so signs and symptoms may develop years after a heart murmur is first heard. Many people who have heart valve disease don't have any symptoms until they're middle-aged or older.

    Other common signs and symptoms of heart valve disease relate to heart failure, which heart valve disease can eventually cause. These symptoms include:
    • Unusual fatigue (tiredness)
    • Shortness of breath, especially when you exert yourself or when you're lying down
    • Swelling of your ankles, feet, or sometimes the abdomen

    Other signs and symptoms

    Heart valve disease can cause chest pain that may only happen when you exert yourself. You also may notice a fluttering, racing, or irregular heartbeat. Some types of heart valve disease, such as aortic or mitral valve stenosis, can cause dizziness or fainting.


    How is heart valve disease diagnosed?

    Your primary care provider may detect a heart murmur or other signs of heart valve disease. However, a cardiologist will usually diagnose the condition. A cardiologist is a doctor who specializes in treating heart problems.

    To diagnose heart valve disease, your doctor will ask about your symptoms. (See previous section.)

    He or she also will do a physical exam and look at the results of medical tests and imaging.


    Physical exam

    Your doctor will listen to your heart with a stethoscope to find out if you have a heart murmur that's likely caused by a heart valve problem.

    Your doctor also will listen to your lungs as you breathe to check for fluid buildup. He or she will check for swollen ankles and other signs that your body is keeping in water.


    Tests and procedures

    The main test for diagnosing heart valve disease is echocardiography. But an EKG (electrocardiogram) or chest X-ray is commonly used to reveal certain signs of the condition. If these signs are present, echocardiography usually is done to confirm the diagnosis.

    Your doctor also may have you undergo other tests, such as cardiac catheterization, stress testing, or cardiac MRI (magnetic resonance imaging), if you're diagnosed with heart valve disease. These tests and procedures can help your doctor better assess how severe your condition is and plan treatment.


    Electrocardiogram

    This is a simple test that detects and records the electrical activity of your heart. It can detect an irregular heartbeat and signs of a previous heart attack. It can also show whether certain chambers of your heart are enlarged.

    An EKG usually is done in your doctor's office.


    Chest X-ray

    This test can show whether certain sections of your heart are enlarged, whether you have fluid in your lungs, or whether there are calcium deposits in your heart.

    This test helps your doctor learn which type of valve defect you have, how severe it is, and whether you have any other heart problems.


    Echocardiography

    The test uses sound waves to create a moving picture of your heart as it beats. A wand that's placed on the surface of your chest transmits the sound waves. Echoes from the sound waves are converted into pictures of your heart on a computer screen.

    An echocardiogram can show:
    • The size and shape of your heart valves and chambers
    • How well your heart is pumping blood
    • Whether a valve is narrowed or has backflow
    Your doctor may recommend a transesophageal echocardiogram, or TEE, to get a better image.

    For a TEE, the sound wave wand is put on the end of a special tube. The tube is passed down your throat and into your esophagus (the tube leading from your mouth to your stomach). You will be given medicine to relax you during this procedure.


    Cardiac catheterization

    For this procedure, a long, thin, flexible tube called a catheter is put into a blood vessel in your arm, upper thigh (groin), or neck and threaded into your heart. Your doctor uses X-ray images to guide the catheter.

    Through the catheter, your doctor does diagnostic tests and imaging that show whether backflow is occurring through a valve and how fully the valve opens. You're given medicine to help you relax, but you're awake during the procedure.

    Your doctor may order a cardiac catheterization if your signs and symptoms of heart valve disease aren't in line with your echocardiography results. The procedure also can help your doctor assess whether your symptoms are due to specific valve problems or coronary artery disease. All of this information helps your doctor decide the best way to treat you.


    Stress test

    During stress testing, you exercise to make your heart work hard and beat fast while heart tests and imaging are done. If you can't exercise, you'll be given medicine to make your heart work hard and beat fast.

    A stress test can show whether you have signs and symptoms of heart valve disease when your heart is working hard. It can help your doctor assess the severity of your heart valve disease.


    Cardiac MRI

    Cardiac MRI uses a powerful magnet and radio waves to make detailed images of your heart. A cardiac MRI image can confirm information about valve defects or provide more detailed information.

    This information can help your doctor plan your treatment. An MRI also may be done before heart valve surgery to help your surgeon plan for the surgery.


    How is heart valve disease treated?

    The goals of heart valve disease treatment are to:
    • Prevent, treat, or relieve the symptoms of other related heart conditions.
    • Protect your valve from further damage.
    • Repair or replace faulty valves when they cause severe symptoms or become life threatening. Man-made or biological valves are used as replacements.
    Currently, no medicines can cure heart valve disease. However, lifestyle changes and medicines often can successfully treat symptoms and delay complications for many years. Eventually, though, you may need surgery to repair or replace a faulty heart valve.


    Prevent, treat, or relieve the symptoms of other related heart conditions

    To relieve the symptoms of heart conditions related to heart valve disease, your doctor may ask you to quit smoking and follow a healthy eating plan low in salt, cholesterol, and fat.

    Examples of healthy eating plans are the National Heart, Lung, and Blood Institute's Therapeutic Lifestyle Changes (TLC) and Dietary Approaches to Stop Hypertension (DASH) eating plans. TLC is for people who have high blood cholesterol. DASH is for people who have high blood pressure (or for anyone who wants to follow a healthy eating plan).

    Your doctor also may ask you to limit physical activities that make you unusually short of breath and fatigued (tired). He or she also may ask that you limit competitive athletic activity, even if the activity doesn't leave you unusually short of breath or fatigued.

    Your doctor may prescribe medicines to help prevent or treat other related heart conditions, such as heart failure, high blood pressure, irregular heartbeats, coronary artery disease (CAD), and life-threatening blood clots. Heart valve disease can cause these conditions or worsen them.

    People who have heart valve disease are commonly prescribed medicines to:
    • Treat heart failure. Heart failure medicines widen blood vessels and rid the body of too much fluid.
    • Lower blood pressure or blood cholesterol levels.
    • Prevent irregular heartbeats.
    • Thin the blood and prevent clots (for people who have man-made valves). These medicines also are prescribed for mitral stenosis or other valve defects that make you prone to developing blood clots.

    Protect your valve from further damage

    If you've had previous heart valve disease and now have a man-made valve, you may be at increased risk for a heart infection called endocarditis. This infection can worsen your heart valve disease. Even if you don't yet have symptoms of a valve problem, you're at increased risk for this infection.

    To help prevent this serious infection, floss and brush your teeth and see a dentist regularly. Gum infections and tooth decay can cause endocarditis.

    Let your doctors and dentists know if you have a man-made valve or if you've had endocarditis before. They may give you antibiotics before medical or dental procedures (such as surgery or dental cleanings) that could allow bacteria to enter your bloodstream. Talk to your doctor about whether you need to take antibiotics before such procedures.


    Repair or replace heart valves

    Your doctor may recommend repairing or replacing your heart valve(s), even if you do not yet have symptoms of heart valve disease. This can prevent lasting damage to your heart and sudden death.

    Having heart valve repair or replacement depends on a number of factors, including:
    • How severe your valve disease is.
    • Your age and general health.
    • Whether you need heart surgery for other conditions, such as bypass surgery to treat CAD. Bypass surgery and valve surgery can be done at the same time.
    When possible, heart valve repair is preferred over heart valve replacement. Valve repair preserves the strength and function of the heart muscle. People who have valve repair also have a lower risk for endocarditis after the surgery, and they don't need to take blood-thinning medicines for the rest of their lives.

    However, heart valve repair surgery is harder to do than valve replacement. Also, not all valves can be repaired. Mitral valves often can be repaired. Aortic or pulmonary valves often have to be replaced.


    Repairing heart valves

    Heart valves can be repaired by:
    • Separating fused valve flaps
    • Removing or reshaping tissue so the valve can close tighter
    • Adding tissue to patch holes or tears or to increase the support at the base of the valve
    Heart surgeons do most heart valve repair surgeries. Cardiologists do some repair surgeries using cardiac catheterization. Although catheterization procedures are less invasive, they also may not work as well for some patients. You and your doctor will decide whether repair is appropriate and the best procedure for doing it.

    Balloon valvuloplasty. Heart valves that don't open fully (stenosis) can be repaired with surgery or with a less invasive catheter procedure called balloon valvuloplasty. This procedure also is called balloon valvotomy.

    During the procedure, a balloon-tipped tube is threaded through your blood vessels and into the faulty valve in your heart. The balloon is inflated to help widen the opening of the valve. Your doctor then deflates the balloon and removes both it and the tube.

    You're awake during the procedure, which usually requires an overnight stay in the hospital.

    Balloon valvuloplasty relieves many of the symptoms of heart valve disease, but it may not cure it. The condition can still worsen over time. You may need medicines to help with symptoms or surgery to repair or replace the faulty valve.

    Balloon valvuloplasty has a shorter recovery time than surgery. For some patients who have mitral valve stenosis, it may work as well as surgical repair or replacement. For these reasons, balloon valvuloplasty usually is preferred over surgical repair or replacement for these people. Balloon valvuloplasty doesn't work as well as surgical treatment for adults who have aortic valve stenosis.

    Balloon valvuloplasty often is used in infants and children. In these patients, valve stenosis is caused by a congenital defect that can be repaired by a one-time procedure.


    Replacing heart valves

    Sometimes heart valves can't be repaired and must be replaced. This surgery involves removing the faulty valve and replacing it with a man-made valve or a biologic valve.

    Biologic valves are made from pig, cow, or human heart tissue and may have man-made parts as well. These valves are specially treated, so no medicines are needed to stop the body from rejecting the valve.

    Man-made valves are more durable than biologic valves and usually don't have to be replaced. Biologic valves usually have to be replaced after about 10 years, although newer biologic valves may last 15 years or longer.

    Unlike biologic valves, however, man-made valves require you to take blood-thinning medicines for the rest of your life. These medicines prevent blood clots from forming on the valve. Blood clots can cause a heart attack or stroke. Man-made valves also raise your risk for endocarditis.

    You and your doctor will decide together whether you should have a man-made or biologic replacement valve. If you're a woman of childbearing age or if you're athletic, you may prefer a biologic valve so you don't have to take blood-thinning medicines. If you're elderly, you also may prefer a biologic valve, as it will likely last for the rest of your life.


    Other approaches for repairing and replacing heart valves

    Some newer forms of heart valve repair or replacement surgery are less invasive than traditional surgery. These procedures use smaller incisions (cuts) to reach the heart valves. Hospital stays for these newer types of surgery are usually 3 to 5 days, compared to 5 day stays for traditional heart valve surgery.

    New surgeries tend to cause less pain and have a lower risk of infection. Recovery time also tends to be shorter – 2 to 4 weeks versus 6 to 8 weeks for traditional surgery.

    Some cardiologists and surgeons are exploring procedures that use cardiac catheterization to thread clips or other devices in a tube through your blood vessels and into the faulty valve in your heart. The clips or devices are used to reshape the valve and stop the backflow of blood. It's not yet known how effective these procedures are.

    The Ross operation is a surgical procedure to treat faulty aortic valves. During this operation, your doctor removes your faulty aortic valve and replaces it with your pulmonary valve. The pulmonary valve is then replaced with a pulmonary valve from a deceased human donor.

    This is more involved surgery than typical valve replacement, and it has a greater risk of complications.

    The Ross operation may be especially useful for children because the surgically replaced valves continue to grow with the child. Also, lifelong treatment with blood-thinning medicines isn't required. But in some patients, one or both valves fail to work properly within a few years of the surgery. Experts continue to debate the usefulness of this procedure.

    Serious risks from all types of heart valve surgery vary according to your age, health, the type of valve defect(s) you have, and the surgical procedure(s) performed.


    How can heart valve disease be prevented?

    To prevent heart valve disease caused by rheumatic fever, see your doctor if you have signs of a strep infection. These signs include a red and painful sore throat, fever, and white spots on your tonsils.

    If you do have a strep infection, be sure to take all medicines prescribed to treat it. Prompt treatment of strep infections can prevent rheumatic fever, which damages heart valves.

    It's possible that exercise, diet, and medicines that lower cholesterol also might prevent aortic stenosis (thickening and stiffening of the aortic valve). Researchers continue to study this possibility.

    A heart healthy eating plan, physical activity, other lifestyle measures, or medicines aimed at preventing a heart attack, high blood pressure, or heart failure also might help prevent heart valve disease.

    If you've had previous heart valve disease and now have a man-made valve, you may be at higher risk for a heart infection called endocarditis. Floss and brush your teeth regularly. Gum infections and tooth decay can cause endocarditis.

    Let your doctors and dentists know if you have a man-made valve or if you've had endocarditis before. They may give you antibiotics before medical or dental procedures (such as surgery or dental cleanings) that could allow bacteria to enter your bloodstream. Talk to your doctor about whether you need to take antibiotics before such procedures.


    Living with heart valve disease

    Heart valve disease is a lifelong condition. However, many people with the condition don't have any symptoms until they're middle-aged or older. Over time, heart valve disease may worsen and can cause heart failure or other life-threatening conditions.

    Eventually, you may need your faulty heart valve(s) repaired or replaced. After repair or replacement, you will still need certain medicines and regular checkups with your doctor.


    Ongoing health care needs

    • See your doctor regularly for checkups and for echocardiography or other tests. This will allow your doctor to check the progress of your heart valve disease. Ask your doctor what physical activities are appropriate for you.

    • Call your doctor if your heart valve disease symptoms worsen or you develop new symptoms.

    • Call your doctor if you develop symptoms of endocarditis. Symptoms of this heart infection include fever, chills, muscle aches, night sweats, difficulty breathing, fatigue (tiredness), weakness, red spots on the palms and soles, and swelling of the feet, legs, and belly.

    • Let your doctors and dentists know if you have a man-made valve or if you've had endocarditis before. They may give you antibiotics before medical or dental procedures (such as surgery or dental cleanings) that could allow bacteria to enter your bloodstream. Talk to your doctor about whether you need to take antibiotics before such procedures.

    • Take all your prescribed medicines.

    Pregnancy and heart valve disease

    Mild to moderate heart valve disease during pregnancy usually can be managed with medicines or bed rest without posing heightened risks to the mother or fetus.

    Most heart valve conditions can be treated with medicines that are safe to take during pregnancy. Your doctor can advise you on which medicines are safe for you.

    Severe heart valve disease can make pregnancy or labor and delivery riskier. If you have severe heart valve disease and/or its symptoms, consider having your heart valves repaired or replaced before getting pregnant. Such repair or replacement also can be done during pregnancy, if needed. But this surgery poses danger to both the mother and fetus.


    Related categories

       • HEART TOPICS
       • HEALTH AND DISEASE

    Source: U.S. National Heart, Lung and Blood Institute