Endocarditis is a very serious heart condition that happens when the inner lining of the heart or the heart valves become inflamed. In most cases, this inflammation is caused by an infection.

When bacteria or other germs enter the bloodstream and reach the heart, they can grow there and damage the heart tissue. This may lead to holes in the heart valves and other serious problems.

Endocarditis is rare. Each year, almost 3 to 7 people in 100,000 in developed countries are diagnosed with it. However, the condition has become more common in recent years, especially as more older adults undergo surgeries. Medical procedures can increase the risk of infection, which in turn can lead to endocarditis.

Endocarditis Signs and Symptoms

Endocarditis usually causes a fever along with other symptoms, which can range from mild to severe. Because the symptoms of endocarditis often look like those of other illnesses, such as the flu, it’s sometimes hard to recognize endocarditis right away.

Symptoms and signs of endocarditis may include:

• Fever, chills, or night sweats
• Tiredness
• Rash
• Headaches
• Persistent cough
• Chest pain when breathing
• Swelling or bloating
• Shortness of breath
• Muscular pain or weakness
• Wounds or sores that are discolored, drain pus, or don’t heal
• Discolored spots inside the mouth
• Unexpected weight loss

Less common symptoms can include:

• Pain in the upper left part of the belly
• Blood in the urine (may look red or brown)
• Osler nodes or Janeway lesions — Small, painful bumps or spots on the palms, fingers, soles, or toes that may look red, purple, or brown (depending on skin tone)

If you’re at high risk of endocarditis and experience any of these symptoms, contact your doctor right away. Without treatment, endocarditis can cause serious problems such as an irregular heartbeat, heart failure, stroke, or sepsis (a life-threatening reaction to infection that can damage organs).

Risk Factors and Causes of Endocarditis

Endocarditis happens when germs like bacteria or fungi enter your bloodstream and travel to your heart, where they start to grow. When this is caused by bacteria, it’s called bacterial endocarditis or infective endocarditis.

Typically, these germs come from your skin, mouth, digestive system (gut), or airways. The bacteria can move into your bloodstream when you eat, brush your teeth, floss, have a bowel movement, or perform other everyday activities.

You’re more likely to experience endocarditis if you have:

• A congenital (present at birth) heart defect or heart valve disease
• An artificial heart valve
• A medical device in your heart, such as a pacemaker
• A condition that requires you to use an intravenous (IV) line or catheter
• A history of using IV or injectable drugs
• Surgery involving your airways, urinary tract, digestive system, or mouth
• A weakened immune system
• Ongoing dental problems
• Tattooing or piercing done in unclean or unsafe conditions

If you’ve had endocarditis in the past, you’re more likely to get it again. The risk also increases with age.

Diagnosis of Endocarditis

Your doctor may order several tests to look for signs of infection or heart problems.

Blood tests check for bacteria and signs of inflammation, such as a high level of C-reactive protein. Higher levels of white blood cells may indicate an infection.

Your doctor may also do an echocardiogram (echo), a test that uses sound waves to produce a picture of your heart. You might have either a transthoracic echo (placing a device on your chest) or a transesophageal echo (placing a probe in your esophagus, the tube that connects your mouth to your stomach). These tests show signs of swelling, abscesses (pockets of pus), growths, leaking, or other heart valve problems.

An electrocardiogram (ECG) may also be used. An ECG tracks your heart’s electrical signals to see if your heartbeat is affected. Other imaging tests such as a chest X-ray, MRI, or CT scan can help doctors see if the infection is affecting other parts of your body.

Endocarditis Treatments

Because endocarditis is usually caused by a bacterial infection, antibiotic therapy is often a part of treatment. The antibiotics are given at high doses through an IV line. You may need multiple antibiotic treatments over several weeks. Antifungal medication is used if a fungus is causing the infection.

Sometimes, endocarditis damages the heart so much that surgery may be necessary. Surgical procedures can repair or replace damaged heart valves that no longer work properly. You may get an artificial valve or a valve replacement from a pig, cow, or human.

As you undergo treatment, watch for signs that your endocarditis is worsening. Let your doctor know right away if you notice symptoms like fever, joint pain, headaches, or breathing difficulties. These could be signs that the infection is getting worse.

Can Endocarditis Be Prevented?

If you have certain heart conditions or other risk factors, your doctor may recommend taking antibiotics before some medical or dental procedures. This is called prophylactic antibiotic use — medicine used to prevent an infection before it starts. Not everyone needs this kind of treatment, so it’s important to talk with your doctor to see if it’s right for you.

Practicing good oral health can also help reduce your risk. Brush twice a day, floss your teeth daily, and visit your dentist regularly for cleanings and checkups.

Talk With Others Who Understand

On MyHeartDiseaseTeam, the social network for people living with heart disease and their loved ones, members come together to ask questions, give advice, and share their stories with others who understand life with heart disease.

Have you been diagnosed with endocarditis? What symptoms did you have? Share your experience in the comments below, or start a conversation by posting on your Activities page.