The inside of your heart contains four chambers and four valves lined by a thin membrane called the endocardium. Endocarditis is an infection of this inner lining.
Endocarditis typically occurs when bacteria 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. Left untreated, endocarditis can damage or destroy your heart valves. Endocarditis can be life-threatening.
Endocarditis is uncommon in people with healthy hearts. People at greatest risk of endocarditis have a damaged heart valve, an artificial heart valve or other heart defects.
Endocarditis may develop slowly or suddenly — depending on what's causing the infection and whether you have any underlying heart abnormalities.
Signs and symptoms of endocarditis may include:
Sometimes endocarditis causes red, tender spots under the skin of the fingers. These are known as Osler's nodes. You may notice tiny purple or red spots known as petechiae (puh-TE-ke-e) on other areas of the skin. Similar spots may appear in the whites of your eyes or inside your mouth.
Endocarditis occurs when germs enter your bloodstream, travel to your heart, and attach to abnormal heart valves or damaged heart tissue. Bacteria are the cause of most cases, but fungi or other microorganisms also may be responsible.
Sometimes the culprit is one of many common bacteria that live in your mouth, upper respiratory tract or other parts of your body. In other cases, the offending organism may gain entry to your bloodstream through:
Typically, your immune system destroys bacteria that make it into your bloodstream. Even if bacteria reach your heart, they may pass through without causing an infection.
Most people who develop endocarditis have a diseased or damaged heart valve — an ideal spot for bacteria to settle. This damaged tissue in the endocardium provides bacteria with the roughened surface they need to attach and multiply.
If your heart is healthy, you're unlikely to develop endocarditis. Even most types of heart disease don't increase the risk of endocarditis. The organisms that cause infection tend to adhere to and multiply only in malformed, damaged or surgically implanted heart valves.
Those at highest risk of endocarditis are those who have:
If you have a known heart defect or heart valve problem, ask your doctor about your risk of developing endocarditis. Even if your heart condition has been repaired or hasn't caused symptoms, you may still be at risk.
Some people without heart problems are at risk of endocarditis as well. Intravenous drug users have a greater risk of infection because sharing or reusing needles can expose the bloodstream to infectious agents. People who are hospitalized with IV tubes also may be exposed to infection.
If you develop signs or symptoms of endocarditis, see your doctor right away — especially if you have risk factors for this serious infection. Signs and symptoms may include:
Although less serious conditions can cause similar signs and symptoms, you won't know for sure until you see a doctor.
Your doctor may suspect endocarditis based on your medical history and physical signs and symptoms, such as fever. Using a stethoscope to listen to your heart, your doctor may hear a new heart murmur or a change in a previous heart murmur — possible signs of endocarditis.
The infection can mimic other illnesses in its early stages. Various tests may be necessary to help make the diagnosis:
Endocarditis can cause clumps of bacteria and cellular debris (vegetations) to form in your heart at the site of the infection. These clumps can break loose and travel to your brain, lungs, abdominal organs or kidneys. This may cause various problems, including stroke or damage to other organs.
Left untreated, endocarditis can damage your heart valves and permanently destroy your heart's inner lining. This can cause your heart to work harder to pump blood eventually causing heart failure — a chronic condition in which your heart is unable to pump enough blood to meet your body's needs. If the infection progresses untreated, it's usually fatal.
If you have endocarditis, you may need high doses of intravenous antibiotics in the hospital. Blood tests may help identify the type of microorganism that's infecting your heart. This information will help your doctor choose the best antibiotic or combination of antibiotics to fight the infection.
You may need to take antibiotics for two to six weeks to clear up the infection. Once your fever and the worst of your signs and symptoms have passed, you may be able to leave the hospital and continue antibiotic therapy in an outpatient setting. You'll need to see your doctor regularly to make sure your treatment is working.
Report to your doctor any signs or symptoms that your infection is getting worse, such as:
Diarrhea, a rash, itching or joint pain may indicate a reaction to an antibiotic — another reason to call your doctor.
See your doctor immediately if you experience shortness of breath or swelling in your legs, ankles or feet. These signs and symptoms may indicate heart failure.
If the infection damages your heart valves, you may have symptoms and complications for years after treatment. Sometimes surgery is needed to treat persistent infections or replace a damaged valve.
People with the following heart conditions are at risk of more serious outcomes from endocarditis:
People with these conditions may need to take preventive antibiotics before certain medical or dental procedures to prevent endocarditis.
Preventive antibiotics
Certain dental and medical procedures may allow bacteria to enter your bloodstream. Antibiotics taken before these procedures can help destroy or control the harmful bacteria that may lead to endocarditis.
New guidelines released in 2007 reserve preventive antibiotic treatment only for those people who would have the worst outcomes if they get infective endocarditis. As a result, the list of procedures for which antibiotics are recommended has grown shorter. Antibiotics are now recommended only before the following:
Antibiotics are no longer recommended before all dental procedures or for procedures of the urinary tract or gastrointestinal system.
If you've had to take preventive antibiotics in the past before your dental exams, you may be concerned about these changes. In the past, you were likely told to get antibiotics because of a concern that common dental procedures increased your risk of endocarditis. But as doctors have learned more about endocarditis prevention, they've realized that endocarditis is much more likely to occur from exposure to random germs than from a typical dental exam or surgery.
As a result of this new knowledge, doctors now know few people would benefit from receiving preventive antibiotics before a dental exam in an effort to prevent endocarditis. Part of the reason for the change is that although the risk of receiving antibiotic treatment is small, adverse reactions and even life-threatening reactions can occur.
This doesn't mean it's not important to take good care of your teeth through brushing and flossing. There is some concern that infections in your mouth from poor oral hygiene might increase the risk of germs entering your bloodstream. In addition to brushing and flossing, regular dental exams — at least get a yearly exam — are an important part of maintaining good oral health.
Still, if you have been told to take antibiotics before any procedures in the past, check with your doctor to see how these recommendations apply to you.
If you're at risk of endocarditis, let all of your health care providers 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 Web site.
To help prevent endocarditis, take good care of yourself. Pay special attention to your dental health. Brush and floss your teeth and gums often, and schedule regular dental checkups. Avoid procedures that may lead to skin infections, such as body piercing or tattoos. Seek prompt medical attention if you develop any type of skin infection or open cuts or sores that do not heal properly.
