Topic Overview
What is dilated cardiomyopathy?
Dilated cardiomyopathy
is a serious condition that weakens your heart muscle and
causes it to stretch, or dilate. When your heart muscle is weak, it can't pump
out blood as well as it should, so more blood stays in your heart after each
heartbeat. As more blood fills and stays in the heart, the heart muscle
stretches even more and gets even weaker.
Most of the time, this
leads to
heart failure. Heart failure does not mean that your
heart stops pumping. It means that your heart can't pump enough blood to meet
your body's needs.
What causes dilated cardiomyopathy?
The most
common type of dilated cardiomyopathy develops after a heart attack has damaged
the heart muscle. But it can also be caused by many diseases or problems that
may or may not be related to your heart. Sometimes the cause is not known.
Some of the things that can lead to dilated cardiomyopathy
include:
-
Coronary artery disease
and
heart attack.
-
High blood pressure
, which can put stress on the heart walls.
- Heart
valve diseases, including
aortic valve regurgitation and
mitral valve regurgitation.
- Myocarditis,
which is inflammation of the heart muscle. It is caused by a virus or an immune
system problem.
- Drinking too much alcohol, using certain illegal drugs such as
cocaine, or taking certain medicines such as
chemotherapy.
- Being exposed to toxic
metals, such as lead or mercury.
- Being pregnant. In rare cases,
dilated cardiomyopathy develops toward the end of pregnancy or during the first
6 months after a woman gives birth. Experts don't know why this happens.
What are the symptoms?
You may not have any
symptoms at first. Or you may have mild symptoms, such as feeling very tired or
weak.
If your heart gets weaker, you will develop heart failure.
When this happens, you will feel other symptoms, including:
- Shortness of breath, especially with
activity.
- Tiredness.
- Trouble breathing when you lie
down.
- Swelling in your legs.
- Chest pain.
You may get these symptoms slowly, over months or years.
Or you may get them suddenly, such as after pregnancy or an illness caused by a
virus.
Heart failure that suddenly gets worse is an emergency. Get
medical help right away if you:
- Have severe shortness of
breath.
- Have a fast or uneven heartbeat.
- Cough up
foamy, pink mucus.
- Have chest pain.
How is dilated cardiomyopathy diagnosed?
Your
doctor will ask questions about your symptoms and past health. He or she will
want to know about recent illnesses and about heart disease in your family.
Your doctor will listen to your heart and lungs and check your legs for fluid
buildup.
You may also have other tests, including:
In some cases, a doctor may want to look at a small
sample of heart tissue, called a biopsy, to make a definite diagnosis.
How is it treated?
You will probably need to take
several medicines to treat heart failure caused by dilated cardiomyopathy. It
is very important to take your medicines exactly as your doctor tells you to
and to keep taking them. If you don't, your heart failure could get worse.
Lifestyle changes are an important part of your treatment. Taking
these steps can help slow down heart failure.
- Limit how much salt you eat. Salt causes
water to build up in your body and makes it harder for your heart to pump.
Limit your fluid intake if your doctor tells you to.
- Get regular
exercise. Your doctor can tell you what level of exercise is safe for you, how
to check your pulse rate, and how to know if you are doing too
much.
- Limit how much alcohol you drink.
Your doctor may suggest a mechanical device to help your
heart pump blood or prevent life-threatening irregular heart rhythms. Such
devices include a
pacemaker,
implantable cardioverter-defibrillator (ICD), or a
combination pacemaker and ICD. If your condition is very bad, a heart
transplant may be an option.
Keeping track of your symptoms every
day is an important part of your treatment. Call your doctor if:
- You have a sudden weight gain such as
3 lb (1.4 kg) or more in 2 to 3
days.
- Your ability to exercise changes.
- You have
any sudden change in your symptoms.
What can you expect with dilated cardiomyopathy?
Most of the time, dilated cardiomyopathy leads to heart failure. Heart
failure usually gets worse over time, but treatment can slow the disease and
help you feel better and live longer. In more and more cases, the problem is
being found earlier, when it can be better managed.
Some people
develop other problems, including:
-
Stroke
.
- Heart attack.
- Sudden cardiac death, which means the heart suddenly stops
working. This may be more likely to happen to people who have serious rhythm
problems (arrhythmias) in one of the lower heart chambers (ventricles).
If a woman gets dilated cardiomyopathy from pregnancy,
she should not get pregnant again. This is true even if her heart problem later
gets better.
If your disease is getting worse over time, you may
want to think about making end-of-life decisions. It can be comforting to know
that you will get the type of care you want.
Frequently Asked Questions
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Being diagnosed:
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Getting treatment:
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Living with dilated cardiomyopathy:
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End-of-life issues:
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Symptoms
Initially you may not feel any symptoms of
dilated cardiomyopathy, or symptoms such as fatigue or
weakness may be mild.
Eventually, you will develop
heart failure. Symptoms of heart failure can develop
gradually, over months or years. In other instances, heart failure may develop
suddenly, such as after a viral infection or pregnancy.
Symptoms of gradual heart failure
Typically,
symptoms of heart failure develop gradually and may include:
- Weakness and fatigue.
- Difficulty
breathing and/or wheezing during normal activities or exercise that did not
cause breathing problems in the past.
-
Shortness of breath.
- A dry, hacking cough,
especially when lying down.
- Fluid buildup (edema), especially in
the legs, ankles, and feet.
- Dizziness, fainting, or feeling tired
or weak.
-
Heart palpitations
.
- Rapid
weight gain caused by water retention.
- Increased urination at
night.
- Abdominal swelling, tenderness, or pain, which may result
from a buildup of fluid in the body (ascites) and blood that backs up in the
liver.
Symptoms of sudden heart failure
In sudden heart
failure, rapid fluid buildup in the lungs may cause symptoms of
pulmonary edema, such as:
- Severe shortness of
breath.
- Irregular or rapid heartbeat.
- Coughing up
foamy, pink mucus.
Sudden heart failure is an emergency medical situation and requires immediate care.
Complications of dilated cardiomyopathy
Complications of dilated cardiomyopathy may include:
-
Pulmonary edema
, which is rapid fluid buildup in the lungs.
-
Arrhythmias
, which are abnormal heart rhythms that can
cause loss of consciousness or sudden death.
- Blood clots inside the
heart, which can lead to a
strokeor
heart attack.
Dilated cardiomyopathy is the most common type of
cardiomyopathy. Other forms of cardiomyopathy include restrictive
cardiomyopathy, in which the heart muscle gets stiff, and hypertrophic
cardiomyopathy, in which the heart muscle is thickened and can't relax. For
more information, see the topics
Hypertrophic Cardiomyopathy and
Restrictive Cardiomyopathy.
Exams and Tests
The first step in diagnosing
dilated cardiomyopathy is a review of your medical
history. Your doctor will ask about any recent illnesses, your alcohol and drug
consumption, and your family history of heart disease.
Then he or
she will do a thorough physical examination, including listening to your heart
and lungs with a stethoscope. Since
heart failure usually develops with dilated
cardiomyopathy, your doctor will look for signs of heart failure,
including:
- Unusual sounds, called
heart murmurs, which may mean you have a problem with
the heart's walls or valves. Pulmonary rales—crackles or bubbling sounds—heard
in the chest may mean there is fluid buildup in the lungs.
- Fluid
buildup may also be noted in the extremities, especially the legs and feet, and
in bulging neck veins.
The following tests may also be done.
Echocardiogram: An
echocardiogram is an
ultrasound exam that uses high-pitched sound waves to
create an image of the heart on a television screen. This painless and
noninvasive test is the best and easiest way to diagnose dilated
cardiomyopathy.
An echocardiogram, sometimes called an echo,
estimates the heart's
ejection fraction, a measurement of the heart's
efficiency and the function of the left ventricle, the main pumping chamber. It
also helps evaluate heart valve function and the shape and thickness of the
heart chamber walls, which if stretched may indicate
dilated cardiomyopathy.
Electrocardiogram:
An
electrocardiogram (ECG, EKG) is a record of the
heart's electrical activity, including any abnormal heart rhythms (arrhythmias)
resulting from dilated cardiomyopathy. It may also reveal areas that have been
damaged by a heart attack.
Your doctor may also use a
Holter monitor, a type of portable electrocardiogram
that monitors your heart's electrical activity over a longer period of time
(usually 24 hours). This may be done to check for any arrhythmias resulting
from dilated cardiomyopathy.
Chest X-ray: A
chest X-ray can show whether your heart is enlarged
and whether there is fluid buildup in your lungs, a sign of heart
failure.
Radionuclide ventriculogram:
Radionuclide ventriculogram, also called nuclear
scanning, measures ejection fraction. This is a useful diagnostic measurement
because the ejection fraction is diminished in dilated cardiomyopathy.
During this test, a tiny dose of a radioactive substance (radioisotope)
is injected into a vein. The movement of the gamma rays emitted by the
radioisotope is followed through the heart chambers with a gamma camera, and
the images are analyzed by a computer.
Coronary angiogram or coronary catheterization: In a
coronary angiogram/catheterization, a thin, flexible
tube is threaded through an artery or vein in the arm or groin and into the
heart to measure pressure in the heart chambers and take samples of blood. Dye
can also be injected through the catheter to see whether the arteries that
supply the heart (coronary arteries) are blocked, how the heart chambers are
pumping, and whether heart valves are leaking.
A myocardial
biopsy, a sample of heart tissue, can be taken through the catheter and
examined for signs of infection, metabolic disease, or a tumor. This procedure
is usually reserved for people who have acute heart failure and who are not
responding to treatment.
Electrophysiology study: An
electrophysiology study (EP, EPS) is another way to
study the heart's electrical activity. EP studies are used to evaluate
arrhythmias or
syncope and to assess the risk of sudden cardiac
death.
For more information about exams and tests, see the topic
Heart Failure.
Treatment Overview
In most cases, treatment for
dilated cardiomyopathy is done to relieve symptoms,
improve heart function, and help you live longer. The majority of people will
need to take a number of medicines along with making healthy lifestyle changes.
Surgical procedures may also be considered, especially when medicines do not
improve your condition.
In some cases, the cause of the condition
can be successfully addressed, such as when dilated cardiomyopathy is caused by
excessive alcohol consumption. Limiting how much you drink may help prevent the
disease from progressing.
But in viral myocarditis (inflammation
of the heart muscle caused by a virus), there are no medicines to attack the
viruses that cause dilated cardiomyopathy.
Medications
Medicines used to treat
heart failure caused by dilated cardiomyopathy
include:
-
Angiotensin-converting enzyme (ACE) inhibitors,
angiotensin II receptor blockers (ARBs), and
vasodilators, which widen blood vessels to improve
blood flow and reduce the heart's workload. ACE inhibitors are considered the
basis of therapy for dilated cardiomyopathy. They specifically have been shown
to improve symptoms and prolong life in people who have heart failure. ARBs may
be used when a person cannot tolerate ACE inhibitors or the medicine is not
controlling symptoms. Other vasodilators may be used when a person cannot
tolerate ACE inhibitors or ARBS or the medicines are not controlling
symptoms.
-
Beta-blockers, which slow the heart rate and reduce
blood pressure. The heart can pump more efficiently when it has more time to
relax. Adding beta-blockers to standard treatment with ACE inhibitors may
reduce the rate of hospitalization or death in people with moderate or severe
heart failure.
-
Diuretics, to help remove excess fluid
from the body. Spironolactone is a diuretic that prevents potassium loss and
has been shown to prolong life in people with severe forms of heart
failure.
-
Digoxin, which can help increase the strength of the
heart muscle contraction, improve blood flow, and reduce symptoms of heart
failure.
-
Anticoagulants, such as warfarin (for example,
Coumadin) and heparin, to prevent blood clots that can develop when blood is
not being pumped efficiently through the heart and out to the rest of the body.
Blood clots may lead to strokes or heart attack. People with both dilated
cardiomyopathy and
atrial fibrillation are at higher risk for developing
blood clots.
-
Antiarrhythmics
, such as amiodarone,
which control the heart rate when abnormal, rapid heartbeats (arrhythmias) are present.
For more information on these medicines, see the topic
Heart Failure.
Surgery
A
pacemaker for heart failure may be surgically placed
in the upper chest. This pacemaker helps your heart pump blood. This pacemaker
makes both lower chambers of the heart (ventricles) pump blood at the same
time. Because both ventricles beat at the same time, this pacemaker is also
called a biventricular pacemaker. It can help you feel better so you can be
more active. It also can help keep you out of the hospital and help you live
longer.1 This pacemaker is also called cardiac
resynchronization therapy. Sometimes this pacemaker is combined with an
implantable cardioverter-defibrillator (ICD) to
prevent sudden death from a life-threatening irregular heartbeat.
An
implantable cardioverter-defibrillator (ICD) is a
small device that is surgically implanted in the chest. It is used to lower the
risk of sudden death from life-threatening irregular heart rhythms (arrhythmias). An ICD continuously monitors your heart.
If it detects a life-threatening rapid heart rhythm, it sends an electric shock
to your heart to restore a normal rhythm. You may need an ICD if you have had a
serious episode of life-threatening irregular heart rhythm or are at high risk
for having one.
Ventricular assist devices (VADs), also known as heart
pumps, are mechanical pumping devices that are inserted into the chest to help
the heart pump more blood. VADs are typically used to keep people alive until a
donor heart is available for transplant. Rarely, VADs may be used as an
alternative to heart transplant for long-term treatment of severe heart
failure. These devices require surgery to place the device and to make the
connections between the heart and the device. See picture of a
ventricular assist device.
A
heart transplant is the only cure for dilated
cardiomyopathy. But a transplant is available to a small number of people who
meet specific criteria for transplantation. The diseased heart is removed and
replaced with a healthy heart donated by a person who has recently died. There
are limited donor hearts available.
Mitral valve repair or replacement. This surgery is
standard practice for mitral valve problems, but not for dilated
cardiomyopathy. Sometimes, dilated cardiomyopathy can lead to
mitral valve regurgitation. Surgery on the mitral
valve can treat the regurgitation, but it does not cure dilated
cardiomyopathy.
Home Treatment
Even though medical care is very
important in treating
dilated cardiomyopathy, the following self-care
recommendations are also important.
- Limit alcohol. Drink moderately, which is 2
drinks a day or less for men or 1 drink a day or less for women. Long-term
overuse of alcohol may increase the risk of developing cardiomyopathy in some
people.
- Restrict salt (sodium) in your diet. The body attempts to
compensate for heart failure by retaining salt and water. This leads to fluid
buildup and swelling. For more information, see:
Heart failure: Eating less salt.- Low-salt diets: Eating out.
- Limit fluids if your doctor told you to. Talk to
your doctor about how much fluid is safe for your specific condition. For more
information, see:
- Heart failure: Watching your fluids.
- Weigh yourself daily. If fluid begins to build up rapidly, you
will notice a sudden weight gain. Your doctor may tell you how much weight to
watch for. But in general, call your doctor if you gain
3 lb (1.4 kg) or more in 2 to 3
days. For more information, see:
- Heart failure: Checking your weight.
- Exercise. Your doctor will tell you the kind of
physical activity you can safely do. Most people are encouraged to walk or ride
a bike or do some other kind of exercise, if their condition allows it. For
information on starting and staying with an exercise program, see:
- Heart failure: Activity and exercise.
- Avoid triggers for sudden heart failure. For more
information, see:
- Heart failure: Avoiding triggers for sudden heart failure.
- Take your medicines as directed. If you don't,
your heart failure may get worse, or you may develop
sudden heart failure. For more information, see:
- Heart failure: Taking medicines properly.
- Be careful using nonprescription medicines. Some
medicines can make your heart failure worse. For more information see:
- Heart failure: Avoiding medicines that make symptoms worse.
Pregnancy can be dangerous for people with dilated
cardiomyopathy. If you have dilated cardiomyopathy and are considering becoming
pregnant, talk to your doctor.
For more information on home
treatment, see the topic
Heart Failure.
Other Places To Get Help
Organizations
|
American Heart Association (AHA)
|
| 7272 Greenville Avenue |
| Dallas, TX 75231 |
| Phone: |
1-800-AHA-USA1 (1-800-242-8721) |
| Web Address: |
www.americanheart.org |
| |
|
Call the American Heart Association (AHA) to find your
nearest local or state AHA group. AHA can provide brochures and information
about support groups and community programs, including Mended Hearts, a
nationwide organization whose members visit people with heart problems and
provide information and support. AHA's Web site also has information on
physical activity, diet, and various heart-related conditions.
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National Heart, Lung, and Blood Institute
(NHLBI)
|
| P.O. Box 30105 |
| Bethesda, MD 20824-0105 |
| Phone: |
(301) 592-8573 |
| Fax: |
(240) 629-3246 |
| TDD: |
(240) 629-3255 |
| E-mail: |
nhlbiinfo@nhlbi.nih.gov |
| Web Address: |
www.nhlbi.nih.gov |
| |
|
The U.S. National Heart, Lung, and Blood Institute
(NHLBI) information center offers information and publications about preventing
and treating:
- Diseases affecting the heart and circulation, such as heart
attacks, high cholesterol, high blood pressure, peripheral artery disease, and
heart problems present at birth (congenital heart diseases).
- Diseases that affect the lungs, such as asthma, chronic
obstructive pulmonary disease (COPD), emphysema, sleep apnea, and
pneumonia.
- Diseases that affect the blood, such as anemia,
hemochromatosis, hemophilia, thalassemia, and von Willebrand disease.
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Texas Heart Institute
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| P.O. Box 20345 |
| Houston, TX 77225-0345 |
| Phone: |
1-800-292-2221 (Heart Information Service hotline)
(832) 355-4011 (general line) |
| E-mail: |
his@heart.thi.tmc.edu (Heart Information Services) |
| Web Address: |
www.texasheartinstitute.org |
| |
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The Texas Heart Institute's national telephone hotline is staffed
by medical professionals who can answer heart-related health questions. The Web
site provides information on a wide range of heart topics, including common
disorders and prevention programs.
|
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References
Citations
-
McKelvie R (2008). Heart failure, search date January
2007. Online version of BMJ Clinical Evidence. Also
available online: http://www.clinicalevidence.com.
Other Works Consulted
- Hare JM (2008). The dilated, restrictive, and
infiltrative cardiomyopathies. In P Libby, ed., Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 8th ed., vol. 2,
pp. 1739–1761. Philadelphia: Saunders Elsevier.
- Hunt SA, et al. (2009). 2009 focused update
incorporated into the ACC/AHA 2005 guidelines for the diagnosis and management
of heart failure in adults. A report of the American College of Cardiology
Foundation/American Heart Association Task Force on Practice Guidelines.
Circulation, 119(14): e391–e479.
- Mestroni L, et al. (2008). Dilated cardiomyopathies.
In V Fuster et al., eds., Hurst's the Heart, 12th ed.,
pp. 803–821. New York: McGraw-Hill.
Credits
|
Author
|
Robin Parks, MS |
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Editor
|
Kathleen M. Ariss, MS |
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Associate Editor
|
Pat Truman, MATC |
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Primary Medical Reviewer
|
Caroline S. Rhoads, MD - Internal Medicine |
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Specialist Medical Reviewer
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Stephen Fort, MD, MRCP, FRCPC - Interventional Cardiology |
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Last Updated
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August 20, 2008 |
