Date Updated: 11/14/2020


Endocarditis is a life-threatening inflammation of the inner lining of your heart's chambers and valves (endocardium).

Endocarditis is usually caused by an infection. Bacteria, fungi or other germs from another part of your body, such as your mouth, spread through your bloodstream and attach to damaged areas in your heart. If it's not treated quickly, endocarditis can damage or destroy your heart valves. Treatments for endocarditis include medications and, sometimes, surgery.

People at greatest risk of endocarditis usually have damaged heart valves, artificial heart valves or other heart defects.


Endocarditis may develop slowly or suddenly, depending on what germs are causing the infection and whether you have any underlying heart problems. Signs and symptoms of endocarditis can vary from person to person.

Common signs and symptoms of endocarditis include:

  • Aching joints and muscles
  • Chest pain when you breathe
  • Fatigue
  • Flu-like symptoms, such as fever and chills
  • Night sweats
  • Shortness of breath
  • Swelling in your feet, legs or abdomen
  • A new or changed heart murmur, which is the heart sound made by blood rushing through your heart

Less common signs and symptoms of endocarditis can include:

  • Unexplained weight loss
  • Blood in your urine, which you might be able to see or that your doctor might see when he or she views your urine under a microscope
  • Tenderness in your spleen, which is an infection-fighting organ located just below your left rib cage
  • Red spots on the soles of your feet or the palms of your hands (Janeway lesions)
  • Red, tender spots under the skin of your fingers or toes (Osler's nodes)
  • Tiny purple or red spots, called petechiae (puh-TEE-kee-ee), on the skin, in the whites of your eyes or inside your mouth

When to see a doctor

If you have signs or symptoms of endocarditis, see your doctor as soon as possible — especially if you have risk factors for this serious infection, such as a heart defect or history of endocarditis. Although less serious conditions can cause similar signs and symptoms, you won't know for sure until you're evaluated by your doctor.

If you've been diagnosed with endocarditis, tell your doctor about any signs or symptoms that may mean your infection is getting worse, such as:

  • Chills
  • Fever
  • Headaches
  • Joint pain
  • Shortness of breath

If you're being treated with antibiotics for endocarditis, tell your doctor if you develop diarrhea, a rash, itching or joint pain. These signs and symptoms may mean you're having a reaction to your prescribed antibiotic.


Endocarditis occurs when germs, usually bacteria, enter your bloodstream, travel to your heart, and attach to abnormal heart valves or damaged heart tissue. Fungi or other germs also may cause endocarditis.

Usually, your immune system destroys any harmful bacteria that enter your bloodstream. However, bacteria that live in your mouth, throat or other parts of your body, such as your skin or your gut, can sometimes cause endocarditis under the right circumstances.

Bacteria, fungi and other germs that cause endocarditis might enter your bloodstream through:

  • Improper dental care. Proper toothbrushing and flossing helps prevent gum disease. If you don't take good care of your teeth and gums, brushing could cause unhealthy gums to bleed, giving bacteria a chance to enter your bloodstream. Some dental procedures that can cut your gums also may allow bacteria to enter your bloodstream.
  • Catheters. Bacteria can enter your body through a thin tube that doctors sometimes use to inject or remove fluid from the body (catheter). This is more likely to occur if the catheter is in place for a long period of time. For example, you may have a catheter if you need long-term dialysis.
  • Illegal IV drug use. Contaminated needles and syringes are a special concern for people who use illegal IV drugs, such as heroin or cocaine. Often, individuals who use these types of drugs don't have access to clean, unused needles or syringes.

Risk factors

You're more likely to develop endocarditis if you have faulty, diseased or damaged heart valves. However, endocarditis does occasionally occur in previously healthy people.

You have an increased risk of endocarditis if you have:

  • Older age. Endocarditis occurs most often in older adults over age 60.
  • Artificial heart valves. Germs are more likely to attach to an artificial (prosthetic) heart valve than to a normal heart valve.
  • Damaged heart valves. Certain medical conditions, such as rheumatic fever or infection, can damage or scar one or more of your heart valves, increasing the risk of infection.
  • Congenital heart defects. If you were born with certain types of heart defects, such as an irregular heart or abnormal heart valves, your heart may be more susceptible to infection.
  • Implanted heart device. Bacteria can attach to an implanted device, such as a pacemaker, causing an infection of the heart's lining.
  • A history of endocarditis. Endocarditis can damage heart tissue and valves, increasing the risk of a future heart infection.
  • A history of illegal IV drug use. People who use illegal drugs by injecting them are at a greater risk of endocarditis. The needles used to inject drugs can be contaminated with the bacteria that can cause endocarditis.
  • Poor dental health. A healthy mouth and healthy gums are essential for good health. If you don't brush and floss regularly, bacteria can grow inside your mouth and may enter your bloodstream through a cut on your gums.
  • Long-term catheter use. Having a catheter in place for a long period of time (indwelling catheter) increases your risk of endocarditis.

If you're at risk of endocarditis, let all of your doctors know. You may want to request an endocarditis wallet card from the American Heart Association. Check with your local chapter or print the card from the association's website.


In endocarditis, clumps made of germs and cell pieces form an abnormal mass in your heart. These clumps, called vegetations, can break loose and travel to your brain, lungs, abdominal organs, kidneys, or arms and legs.

As a result, endocarditis can cause several complications, including:

  • Heart problems, such as heart murmur, heart valve damage and heart failure
  • Stroke
  • Pockets of collected pus (abscesses) that develop in the heart, brain, lungs and other organs
  • Blood clot in a lung artery (pulmonary embolism)
  • Kidney damage
  • Enlarged spleen


You can take the following steps to help prevent endocarditis:

  • Know the signs and symptoms of endocarditis. See your doctor immediately if you develop any signs or symptoms, especially a fever that won't go away, unexplained fatigue, any type of skin infection, or open cuts or sores that don't heal properly.
  • Take care of your teeth and gums. Brush and floss your teeth and gums often, and have regular dental checkups. Good dental hygiene is an important part of maintaining your overall health.
  • Don't use illegal IV drugs. Dirty needles can send bacteria into your bloodstream, increasing your risk of endocarditis.

Preventive antibiotics

Certain dental and medical procedures may allow bacteria to enter your bloodstream.

If you're at high risk of endocarditis, the American Heart Association recommends taking antibiotics an hour before having any dental work done.

You're at high risk of endocarditis and need antibiotics before dental work if you have:

  • A history of endocarditis
  • A man-made (prosthetic mechanical) heart valve
  • A heart transplant, in some cases
  • Certain types of congenital heart disease
  • Congenital heart disease surgery in the last six months

If you have endocarditis or any type of congenital heart disease, talk to your doctor and dentist about your risks and whether you need preventive antibiotics.


Your doctor will consider your medical history, your signs and symptoms, and your test results when making a diagnosis of endocarditis. The diagnosis is usually based on several factors instead of a single positive test result or symptom.

Tests used to confirm or rule out endocarditis include:

  • Blood culture test. A blood culture test is used to identify any germs in your bloodstream. Blood culture test results help your doctor choose the most appropriate antibiotic or combination of antibiotics.
  • Complete blood count. This blood test can tell your doctor if you have a lot of white blood cells, which can be a sign of infection. A complete blood count can also help diagnose low levels of healthy red blood cells (anemia), which can be a sign of endocarditis. Other blood tests also may be done to help your doctor determine the diagnosis.
  • Echocardiogram. An echocardiogram uses sound waves to produce images of your heart while it's beating. This test shows how your heart's chambers and valves are pumping blood through your heart. Your doctor may use two different types of echocardiograms to help diagnose endocarditis.

    In a transthoracic echocardiogram, sound waves directed at your heart from a wandlike device (transducer) held on your chest produce video images of your heart in motion. This test lets your doctor see the heart's structure and check it for any signs of damage.

    A transesophageal echocardiogram gives your doctor a closer look at your heart valves. During this test, a small transducer attached to the end of a tube is inserted down the tube leading from your mouth to your stomach (esophagus). This test provides much more detailed pictures of your heart than is possible with a transthoracic echocardiogram.

  • Electrocardiogram (ECG or EKG). An ECG is used to measure the timing and duration of your heartbeats. It isn't specifically used to diagnose endocarditis, but it can show your doctor if something is affecting your heart's electrical activity. During an ECG, sensors that can detect your heart's electrical activity are attached to your chest, arms and legs.
  • Chest X-ray. A chest X-ray can show your doctor the condition of your lungs and heart. It can help determine if endocarditis has caused heart swelling or if any infection has spread to your lungs.
  • Computerized tomography (CT) scan or magnetic resonance imaging (MRI). You may need a CT scan or an MRI scan of your brain, chest or other parts of your body if your doctor thinks that infection has spread to these areas.


Many people with endocarditis are successfully treated with antibiotics. Sometimes, surgery may be needed to fix or replace damaged heart valves and clean up any remaining signs of the infection.


The type of medication you receive depends on what's causing the endocarditis.

High doses of IV antibiotics are used to treat endocarditis caused by bacteria. If you receive IV antibiotics, you'll generally spend a week or more in the hospital so your doctor can determine if the treatment is working.

Once your fever and any severe signs and symptoms have gone away, you might be able to leave the hospital and continue IV antibiotics with visits to your doctor's office or at home with home care. You'll usually take antibiotics for several weeks to clear up the infection.

If endocarditis is caused by a fungal infection, your doctor will prescribe antifungal medication. Some people need lifelong antifungal pills to prevent endocarditis from returning.


Heart valve surgery may be needed to treat persistent endocarditis infections or to replace a damaged valve. Surgery is also sometimes needed to treat endocarditis that's caused by a fungal infection.

Depending on your condition, your doctor may recommend repairing your damaged valve or replacing it with an artificial valve made of cow, pig or human heart tissue (biological tissue valve) or man-made materials (prosthetic mechanical valve).

Preparing for an appointment

The first doctor you see will likely be your family doctor or an emergency room doctor. You may be referred to a doctor or surgeon trained in diagnosing and treating heart conditions (cardiologist).

What you can do

You can help prepare for your appointment by taking these steps:

  • Write down any symptoms you're experiencing. Be sure to note how long you've had particular symptoms. If you've had similar symptoms that have come and gone in the past be sure to include that information.
  • Make a list of your key medical information. Your doctor will need to know about any other recent health problems you've had and the names of all prescription and over-the-counter medications and supplements you're taking.
  • Find a family member or friend who can come with you to the appointment. Someone who accompanies you can help remember what your doctor says.

It's also important to write down any questions you might have before you get to your appointment. For endocarditis, some basic questions you might want to ask your doctor include:

  • What's the most likely cause of my symptoms?
  • What kinds of tests do I need? How do I need to prepare for the tests?
  • What treatment do you recommend?
  • How soon after I begin treatment will I start to feel better?
  • What are the possible side effects?
  • Am I at risk of long-term complications from this condition? Will it come back?
  • How often will I need follow-up for this condition?
  • Do I need to take preventive antibiotics for certain medical or dental procedures?
  • I have other medical conditions. How can I best manage these conditions together?

What to expect from your doctor

Your doctor will probably ask you many questions, including:

  • What are your symptoms?
  • When did your symptoms start? Did they come on suddenly or more gradually?
  • Have you had similar symptoms in the past?
  • Are you having difficulty breathing?
  • Have you recently had an infection?
  • Have you recently had a fever?
  • Have you recently had any medical or dental procedures that used needles or catheters?
  • Have you ever used IV drugs?
  • Have you recently lost weight without trying?
  • Have you been diagnosed with any other medical conditions, especially heart murmurs?
  • Do any of your first-degree relatives — such as parents, siblings or children — have a history of heart disease?

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