What Is Endocarditis?
Endocarditis (EN-do-kar-DI-tis) is an infection of
the inner lining of your heart chambers and valves. This lining is called the
endocardium. The condition also is called infective endocarditis (IE).
The term "endocarditis" also is used to describe an
inflammation of the endocardium due to other conditions. This article only
discusses endocarditis related to infection.
IE occurs if bacteria, fungi, or other germs invade
your bloodstream and attach to abnormal areas of your heart. The infection can
damage the heart and cause serious and sometimes fatal complications.
IE can develop quickly or slowly. How the infection
develops depends on what type of germ is causing it and whether you have an
underlying heart problem. When IE develops quickly, it's called acute infective
endocarditis. When it develops slowly, it's called subacute infective
endocarditis.
Overview
IE mainly affects people who have:
- Damaged or artificial heart valves
- Congenital
heart defects (defects present at birth)
- Implanted medical devices in the heart or blood
vessels
People who have normal heart valves also can get IE.
However, the condition is much more common in people who have abnormal
hearts.
Certain factors make it easier for bacteria to enter
your bloodstream. These factors also put you at higher risk for the infection.
For example, if you've had IE before, you're at higher risk for the infection.
Other risk factors include having poor dental
hygiene and unhealthy teeth and gums, using intravenous (IV) drugs, and having
catheters or other medical devices in your body for long periods.
Common symptoms of IE are fever and other flu-like
symptoms. Because the infection can affect people in different ways, the signs
and symptoms vary. IE also can cause complications in many other parts of the
body besides the heart.
If you're at high risk for IE, seek medical care if
you have signs or symptoms of the infection, especially a fever that persists
or unexplained fatigue (tiredness).
Outlook
IE is treated with antibiotics for several weeks.
You also may need
heart
surgery to repair or replace heart valves or remove infected heart
tissue.
Most people who are treated with the proper
antibiotics recover. But if the infection isn't treated, or if it persists
despite treatment (for example, if the bacteria are resistant to antibiotics),
it's usually fatal.
If you have signs or symptoms of IE, you should see
your doctor as soon as you can, especially if you have abnormal heart
valves.
What Causes Endocarditis?
Infective endocarditis (IE) occurs when bacteria,
fungi, or other germs invade your bloodstream and attach to abnormal areas of
your heart. Certain factors increase the risk of germs attaching to a heart
valve or chamber and causing an infection.
A common underlying factor in IE is a structural
heart defect, especially
faulty
heart valves. Usually your immune system will kill germs in your
bloodstream. However, if your heart has a rough lining or abnormal valves, the
invading germs can attach and multiply in the heart.
Other factors, such as those that allow germs to
build up in your bloodstream, also can play a role in causing IE. Common
activities, such as brushing your teeth or having certain dental procedures,
can allow bacteria to enter your bloodstream. This is even more likely to
happen if your teeth and gums are in poor condition.
Having a catheter or other medical devices inserted
through your skin, especially for long periods, also can allow bacteria to
enter your bloodstream. People who use intravenous (IV) drugs also are at risk
for infections due to germs on needles and syringes.
Bacteria also may spread to the blood and heart from
infections in other parts of the body, such as the gut, skin, or genitals.
Endocarditis Complications
As the bacteria or other germs multiply in your
heart, they form clumps with other cells and matter found in the blood. These
clumps are called vegetations (vej-eh-TA-shuns).
As IE worsens, pieces of the vegetations can break
off and travel to almost any other organ or tissue in the body. There, the
pieces can block blood flow or cause a new infection. As a result, IE can cause
a wide range of complications.
Heart Complications
Heart problems are the most common complication of
IE. They occur in one-third to one-half of all people who have the infection.
These problems may include a new
heart
murmur,
heart
failure, heart valve damage,
heart
block, or, rarely, a
heart
attack.
Central Nervous System Complications
These complications occur in as many as 20 to 40
percent of people who have IE. Central nervous system complications most often
occur when bits of the vegetation, called emboli (EM-bo-li), break away and
lodge in the brain.
There, they can cause local infections (called brain
abscesses) or a more widespread brain infection (called meningitis).
Emboli also can cause a stroke or seizures. This
happens if they block blood vessels or affect the brain's electrical signals.
These complications can cause long-lasting damage to the brain and may even be
fatal.
Complications in Other Organs
IE also can affect other organs in the body, such as
the lungs, kidneys, and spleen.
Lungs. The lungs are especially at
risk when IE affects the right side of the heart. This is called right-sided
infective endocarditis.
A vegetation or blood clot going to the lungs can
cause a pulmonary
embolism and lung damage. Other lung complications include
pneumonia
and a buildup of fluid or pus around the lungs.
Kidneys. IE can cause kidney
abscesses and kidney damage. IE also can cause inflammation of the internal
filtering structures of the kidneys.
Signs and symptoms of kidney complications include
back or side pain, blood in the urine, or a change in the color or amount of
urine. In a small number of people, IE can cause kidney failure.
Spleen. The spleen is an organ
located in the left upper part of the abdomen near the stomach. In as many as
25 to 60 percent of people who have IE, the spleen enlarges (especially in
people who have long-term IE).
Sometimes, emboli also can damage the spleen. Signs
and symptoms of spleen problems include pain or discomfort in the upper left
abdomen and/or left shoulder, a feeling of fullness or the inability to eat
large meals, and hiccups.
Who Is At Risk for Endocarditis?
Infective endocarditis (IE) is an uncommon condition
that can affect both children and adults. It's more common in men than
women.
IE typically affects people who have abnormal hearts
or other conditions that make them more likely to get the infection. In some
cases, IE does affect people who were healthy before the infection.
Major Risk Factors
The germs that cause IE tend to attach and multiply
on damaged, malformed, or artificial heart valves and implanted medical
devices. Certain conditions put you at higher risk for IE. These include:
- Congenital
heart defects (defects that are present at birth). Examples include a
malformed heart or abnormal heart valves.
- Artificial heart valves; an implanted medical
device in the heart, such as a pacemaker wire; or an intravenous (IV) catheter
in a blood vessel for a long time.
- Heart valves damaged by rheumatic fever or
calcium deposits that cause age-related valve thickening. Scars in the heart
from a previous case of IE also can damage heart valves.
- IV drug use, especially if needles are shared or
reused, contaminated substances are injected, or the skin isn't properly
cleaned before injection.
What Are the Signs and Symptoms of Endocarditis?
Infective endocarditis (IE) can cause a range of
signs and symptoms that can vary from person to person. Signs and symptoms also
can vary over time in the same person.
Signs and symptoms differ depending on whether you
have an underlying heart problem, the type of germ causing the infection, and
whether you have acute or subacute IE.
Signs and symptoms of IE may include:
- Flu-like symptoms, such as fever, chills, fatigue
(tiredness), aching muscles and joints, night sweats, and headache.
- Shortness of breath or a cough that won't go
away.
- A new
heart
murmur or a change in an existing heart murmur.
- Skin changes such as:
- Overall paleness.
- Small, painful, red or purplish bumps under
the skin on the fingers or toes.
- Small, dark, painless, flat spots on the
palms of the hands or the soles of the feet.
- Tiny spots under the fingernails, on the
whites of the eyes, on the roof of the mouth and inside of the cheeks, or on
the chest. These spots are from broken blood vessels.
- Nausea (feeling sick to your stomach), vomiting,
a decrease in appetite, a sense of fullness with discomfort on the upper left
side of the abdomen, or weight loss with or without a change in appetite.
- Blood in the urine.
- Swelling in the feet, legs, or abdomen.
How Is Endocarditis Diagnosed?
Your doctor will diagnose infective endocarditis
(IE) based on your risk factors, your medical history and signs and symptoms,
and the results from tests.
Diagnosis of the infection often is based on a
number of factors, rather than a single positive test result, sign, or
symptom.
Diagnostic Tests
The results from
blood
tests,
echocardiography,
and an EKG
(electrocardiogram) can help diagnose IE.
Blood Tests
Blood cultures are the most important blood tests
used to diagnose IE. Blood is drawn several times over a 24-hour period. It's
put in special culture bottles that allow bacteria to grow.
Doctors then identify and test the bacteria to see
which antibiotics will kill them. Sometimes the blood cultures don't grow any
bacteria, but the person still has IE. This is called culture-negative
endocarditis, and it requires antibiotic treatment.
More standard blood tests also are used to diagnose
IE. For example, a complete blood count may be used to check the number of red
and white blood cells in your blood. Blood tests also may be used to check your
immune system and to check for inflammation.
Echocardiography
Echocardiography is a painless test that uses sound
waves to create pictures of your heart. Two types of echocardiography are
useful in diagnosing IE.
Transthoracic (tranz-thor-AS-ik)
echocardiogram. For this painless test, gel is applied to the skin on
your chest. A device called a transducer is moved around on the outside of your
chest.
This device sends sound waves called ultrasound
through your chest. As the ultrasound waves bounce off the structures of your
heart, a computer converts them into pictures on a screen.
Your doctor uses the pictures to look for
vegetations, areas of infected tissue (such as an abscess), and signs of heart
damage.
Because the sound waves have to pass through skin,
muscle, tissue, bone, and lungs, the pictures may not have enough detail. Thus,
your doctor may recommend a transesophageal (tranz-ih-sof-uh-JEE-ul)
echocardiogram (TEE).
Transesophageal echocardiogram. For
this test, a much smaller transducer is attached to the end of a long, narrow,
flexible tube. The tube is passed down your throat. Before the procedure,
you're given medicine to help you relax, and your throat is sprayed with
numbing medicine.
The doctor then passes the transducer down your
esophagus (the passage from your mouth to your stomach). Because this passage
is right behind the heart, the transducer can get clear pictures of the heart's
structures.
EKG
An EKG is a simple, painless test that detects
heart's electrical activity. It shows how fast your heart is beating, whether
your heart rhythm is steady or irregular, and the strength and timing of
electrical signals as they pass through your heart.
An EKG typically isn't used to diagnose IE. However,
it may be done to see whether IE is affecting your heart's electrical
activity.
For this test, soft, sticky patches called
electrodes are attached to your chest, arms, and legs. You lie still while the
electrodes detect your heart's electrical signals. A machine records these
signals on graph paper or shows them on a computer screen. The entire test
usually takes about 10 minutes.
How Is Endocarditis Treated?
Infective endocarditis (IE) is treated with
antibiotics and sometimes with
heart
surgery.
Antibiotics
Antibiotics usually are given for 2 to 6 weeks
through an intravenous (IV) line inserted into a vein. You're often
hospitalized for at least the first week or more of treatment. This allows your
doctor to make sure your infection is responding to the antibiotics.
If you're allowed to go home before the treatment is
done, the antibiotics are almost always continued by vein at home. You'll need
special care if you get IV antibiotic treatment at home. Before you leave the
hospital, your medical team will arrange for you to receive home-based care so
you can continue your treatment.
You also will need close medical followup, usually
by a team of doctors. This team often includes a doctor who specializes in
infectious diseases, a cardiologist (heart specialist), and a heart
surgeon.
Surgery
In some cases, surgery is needed to repair or
replace a damaged heart valve or to help clear up the infection. IE due to an
infection with fungi often requires surgery. This is because this type of IE is
harder to treat than IE due to bacteria.
How Can Endocarditis Be Prevented?
If you're at risk for
infective endocarditis (IE), you can take steps to prevent the infection and
its complications.
- Be alert to the signs
and symptoms of IE. Contact your doctor right away if you have any of these
signs or symptoms, especially a persistent fever or unexplained fatigue.
- Brush and floss your teeth regularly, and have
regular dental checkups. Germs from a gum infection can enter your
bloodstream.
- Avoid body piercing, tattoos, or other procedures
that may allow germs to enter your bloodstream.
New research shows that not everyone at risk for IE
needs to take antibiotics before routine dental exams and certain other dental
or medical procedures.
Let your health care providers, including your
dentist, know if you're at risk for IE. They can tell you whether you need such
antibiotics before exams and procedures.
Key Points
- Endocarditis is an infection of the inner lining
of your heart chambers and valves. The condition also is called infective
endocarditis (IE).
- IE occurs if bacteria, fungi, or other germs
invade your bloodstream and attach to abnormal areas of your heart. The
infection can damage the heart and cause serious and sometimes fatal
complications.
- IE can develop quickly or slowly depending on
what type of germ is causing it and whether you have an underlying heart
problem.
- IE mainly affects people who have damaged or
artificial heart valves,
congenital
heart defects (defects that are present at birth), or implanted medical
devices in the heart or blood vessels.
- IE is an uncommon condition that can affect both
children and adults. Its more common in men than women.
- IE can cause a range of signs and symptoms that
can vary from person to person. Signs and symptoms also can vary over time.
Common symptoms are fever and other flu-like symptoms.
- Your doctor will diagnose IE based on your risk
factors, your medical history and signs and symptoms, and the results from
tests. Diagnosis of the infection often is based on a number of factors, rather
than a single positive test result, sign, or symptom.
- IE is treated with antibiotics and sometimes with
heart
surgery. Antibiotics usually are given for 2 to 6 weeks through an
intravenous (IV) line inserted into a vein. Youre often hospitalized for
at least the first week or more of treatment. In some cases, surgery is needed
to repair or replace a damaged heart valve or to help clear up the
infection.
- If youre at risk for IE, you can take steps
to prevent the infection and its complications. Be alert to the signs and
symptoms of IE. Contact your doctor right away if you have any of these signs
and symptoms. Brush and floss your teeth regularly, and have regular dental
checkups. Avoid body piercing, tattoos, or other procedures that may allow
germs to enter your bloodstream.
- Let your health care providers, including your
dentist, know if youre at risk for IE. They can tell you whether you need
antibiotics before routine dental exams and certain other dental or medical
procedures that can let germs into your bloodstream.
Links to Other Information About Endocarditis
NHLBI Resources
Non-NHLBI Resources
Clinical Trials
|