Heart Infections

Medically Reviewed By William C. Lloyd III, MD, FACS
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What is a heart infection?

A heart infection is a serious infection that can lead to heart damage and life-threatening complications. Bacteria, viruses and, rarely, fungi can cause a heart infection. Other names for this condition include cardiac infection and heart valve infection.

Your heart has three main layers, any of which can be the site of a heart infection. The types of heart infection include:

  • Endocarditis is an infection or inflammation of the endocardium. This is the inner most layer of the heart. The endocardium lines the inside of the four heart chambers and the four heart valves. Endocarditis is the most common type of heart infection. It most often occurs in people with pre-existing valve disease and other heart problems. Treatment usually requires hospitalization.

  • Myocarditis is an infection or inflammation of the myocardium. This is the middle muscular layer of the heart. Viral infections are one of several causes of myocarditis. This type of heart infection is rare.

  • Pericarditis is an infection or inflammation of the pericardium. This is the outer layer or membrane covering the heart. A viral infection is the most common cause. It occurs most often in men age 20 to 50 years from a viral infection. Typically, people recover with rest and treatment of symptoms.

General symptoms of a heart infection include chest pain, fever, and shortness of breath. These symptoms can also be present with a life-threatening condition, such as heart attack. Seek immediate medical care if you, or someone you are with, have these symptoms.

What are the symptoms of a heart infection?

Heart infection symptoms with endocarditis can be obvious and develop quickly. This is acute endocarditis, which can rapidly become serious and life threatening. However, they can also be vague and develop gradually, even over months. This is subacute or chronic endocarditis.

Common symptoms of a heart infection

The most common symptoms of endocarditis are:

Serious symptoms that might indicate a life-threatening condition

In some cases, a heart infection can cause life-threatening complications. Seek immediate medical care (call 911) if you, or someone you are with, have any of these life-threatening symptoms including:

  • Chest pain

  • Confusion, disorientation or difficulty understanding speech

  • Drooping on one side of the face

  • Severe headache

  • Slurred or garbled speech, or inability to speak

  • Sudden vision changes

  • Sudden weakness, numbness or paralysis on one side of the body or face

Even if you do not have these potentially life-threatening symptoms, it is wise to seek medical care for any symptoms of heart infection.

What causes heart infection?

Bacteria are the most common cause of endocarditis. Viral endocarditis and fungal endocarditis are less common. Bacteria cause endocarditis when they enter the bloodstream, travel to the heart, and attach to valves or other surfaces. This can happen as the result of infections in the skin, mouth, lungs, gut or urinary tract. It can also happen when you have gum disease or with certain dental procedures. Getting tattoos or body piercings is another way bacteria can enter the bloodstream.

Heart valves are vulnerable to infection because they do not have a direct blood supply. This makes it difficult for the immune system to reach them. Once an infection begins to grow on a valve, white blood cells have a hard time fighting it.

What are the risk factors for heart infection?

People with the highest risk of developing endocarditis include those with the following conditions:

  • Artificial heart valves or other devices in your heart such as a pacemaker

  • Congenital heart defects

  • Damaged or diseased heart valves

  • Hemodialysis for kidney disease

  • HIV

  • IV drug abuse

  • Personal history of endocarditis

Reducing your risk of heart infection

You may be able to lower your risk of endocarditis by:

  • Avoiding skin infections and keeping cuts and sores clean. Seek medical care for sores that do no heal properly.

  • Keeping your teeth and gums healthy, and getting regular dental care. People with an increased risk of developing endocarditis may need antibiotics before certain dental procedures.

If you are at risk of endocarditis, know the symptoms and seek medical care right away if you have them.

How is a heart infection treated?

Antibiotics are the main treatment for endocarditis. The choice of antibiotic will depend on the specific organism causing the infection. The hospital will run tests to find out this information. Because the infection is inside the heart, your doctor will use IV antibiotics. This requires hospitalization for about a week. Your doctor needs to make sure you are receiving the right antibiotics and give them time to work. You will need IV antibiotics for up to eight weeks to clear the infection. A home health service will administer them after you leave the hospital.

In severe or persistent cases, surgery may be necessary to remove the source of infection and prevent complications. You are more likely to need surgery with fungal endocarditis.

What are the potential complications of heart infection?

Complications of a heart infection can be serious and life threatening. Left untreated, endocarditis can lead to stroke and damage to the heart valves and heart lining. This can also occur in severe cases despite starting antibiotic treatment. Surgery may be necessary to prevent stroke or repair or replace damaged heart valves.

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2020 Aug 21
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