Condition Basics

What is endocarditis?

Endocarditis is an infection of the heart's valves and inner lining of the heart chambers. It occurs when germs get into the bloodstream and settle inside the heart, often on a valve. The infection is usually caused by bacteria. In rare cases, it is caused by fungi.

This infection can damage your heart. It needs to be treated right away. If it isn't treated, endocarditis can be deadly.

What are the symptoms?

Symptoms may appear quickly, within a few days of infection. In other cases, they may develop more slowly. The symptoms will get worse as the bacteria or fungi grow in your heart.

Symptoms may include:

  • Flu-like symptoms such as fever, chills, night sweats, and fatigue. These are often the first symptoms.
  • Weight loss.
  • Muscle or joint pain.
  • Cough.
  • Shortness of breath.
  • Blood under the fingernails or tiny purple and red spots under the skin.

See your doctor if you have symptoms like these that don't go away, especially if you are at risk for endocarditis.

If endocarditis isn't treated soon, it can lead to more serious problems, such as:

How is it diagnosed?

First, your doctor will ask about your medical history and your symptoms. The doctor will also do a physical examination to check for signs of the infection. These signs include a heart murmur, an enlarged spleen, and bleeding under the nails.

Your doctor may also do tests, such as:

  • Blood cultures. These tests look for bacteria in your bloodstream.
  • Echocardiogram. This is done to check your heart for problems such as infected areas or heart valve defects.
  • Electrocardiogram (EKG or ECG). This test checks for heart rhythm problems.
  • A chest X-ray. This is to see if your heart is enlarged or if you have signs of heart failure.
  • An MRI (magnetic resonance imaging) test or a CT scan. These may be done as additional tests to check your heart for problems.

How is endocarditis treated?

Endocarditis is usually treated with antibiotics. You will probably need several weeks of treatment. The antibiotics must be given long enough and at a strong enough dose to destroy all of the bacteria.

At first you will be treated in the hospital. This is so that antibiotics can be given through a vein (IV). After your fever is gone and you are stable, you may be able to continue IV antibiotics at home. A home health nurse can help you with this.

After you have been treated with IV antibiotics, your doctor may want you to take antibiotic pills. If so, take them exactly as prescribed until they are gone. If your symptoms come back, call your doctor right away. You probably will need more antibiotics if testing shows that the bacteria were not completely destroyed.

Some people who have endocarditis need surgery to repair or replace a heart valve or to prevent complications.

You may have follow-up visits for months or years to check the health of your heart.

What increases your risk?

Your risk is higher if you have a problem that affects blood flow through your heart. That's because a blood flow problem makes it more likely that bacteria or fungi will attach to heart tissue. Some other things raise your risk too, because they can let bacteria or fungi enter your bloodstream.

You have a higher risk of endocarditis if you:

  • Have had endocarditis in the past.
  • Have an implanted heart device such as a pacemaker or implantable cardioverter-defibrillator (ICD).
  • Have a hemodialysis access or a central venous catheter.
  • Have abnormal or damaged heart valves.
  • Have had a heart valve replaced or repaired.
  • Have a congenital heart defect.
  • Have injected drugs.

Not all heart problems put you at higher risk for endocarditis. You do not have a higher risk if you have had:

  • Bypass surgery for heart disease.
  • Rheumatic fever without heart valve damage.
  • A heart attack without other complications.
  • Mitral valve prolapse without regurgitation or unusually thickened valve leaflets.
  • A coronary artery stent.

How can you prevent endocarditis?

Endocarditis is most dangerous for people who have:

  • Had a heart valve replaced or repaired.
  • Had endocarditis before.
  • A congenital heart defect.
  • Heart valve problems after a heart transplant.

If you have any of these heart problems, you may need to take antibiotics before you have some kinds of dental work, surgery, or medical procedures. The antibiotics lower your risk of getting endocarditis. Your doctor can give you a wallet card to carry that says you need preventive antibiotics.

It's also very important to take good care of your teeth and gums every day. Good oral care can limit the growth of mouth bacteria that could get into your bloodstream. Practice good oral hygiene by brushing and flossing your teeth daily. See a dentist twice each year.


Current as of: September 7, 2022

Author: Healthwise Staff
Medical Review:
Rakesh K. Pai MD, FACC - Cardiology, Electrophysiology
E. Gregory Thompson MD - Internal Medicine
Martin J. Gabica MD - Family Medicine
Adam Husney MD - Family Medicine
Elizabeth T. Russo MD - Internal Medicine
Robert A. Kloner MD, PhD - Cardiology