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.
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
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