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.

More Information


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).

Clinical trials

Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.

Preparing for your 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?
Nov. 14, 2020
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