Definition: is a disease characterized by inflammation or infection of the inner surface of the heart (the endocardium).
Endocarditis commonly affects the heart valves, but it can also involve nonvalvular areas or mechanical devices that are implanted in the heart, such as artificial heart valves, pacemakers, or implantable defibrillators.
Endocarditis is inflammation of the inner lining of the heart, called the endocardium. This condition is also called infective endocarditis. It is usually caused by bacteria. Endocarditis is rare in people with healthy hearts.
Infective endocarditis is an uncommon but not rare disease that affects around 10,000 to 20,000 people in the United States each year.
Although uncommon, endocarditis is important because, despite antimicrobial therapy, it can lead to serious complications such as stroke, the need for open heart surgery, or even death.
When endocarditis occurs, small masses called vegetations form at the site of infection.
When the vegetations are observed under a microscope, the microorganism causing the infection embedded in a fibrin mesh and other cellular material similar to that used by the body to form blood clots is usually seen.
The white blood cells that the body uses to fight the infection are rare, a finding that explains the need to administer antibiotics for many weeks to eliminate the infecting organism and cure the endocarditis.
The absence of white blood cells in vegetations is not fully explained, but is probably related in part to the dense nature of plant tissue, which in turn restricts the migration of these cells.
In addition, the bacteria that cause endocarditis are buried in an unborn state in deep vegetation. In this state they do not generate the intense chemical signals that usually promote the migration of white blood cells to a site of infection.
Who can get endocarditis?
Endocarditis occurs when bacteria enter the bloodstream (bacteremia) and attach to a damaged portion of the inner lining of the heart or abnormal heart valves.
Not all bacteria that enter the bloodstream are capable of causing endocarditis. Only bacteria that are able to adhere to the surface of the heart lining and abnormal valves tend to cause endocarditis.
The ability of these bacteria to adhere to the surface coating is aided by a preexisting microscopic clot that often forms in these abnormal sites.
Endocarditis occurs more frequently in people with preexisting heart disease (which may or may not be known to patients or their doctors) and less commonly in people with normal hearts.
Pre-existing cardiac conditions associated with bacterial endocarditis
- Previous cardiac valvular surgery.
- Previous infectious endocarditis.
- Prolapse of the mitral valve with valve leakage.
- Abnormal valves caused by rheumatic fever and degenerative conditions.
- Some congenital heart diseases
Some congenital heart defects (eg, ventricular septal defect, atrial septal defect, or patent ductus arteriosus) can be surgically repaired. Once repaired, they are not associated with an increased risk of subsequent endocarditis.
The symptoms of endocarditis are not always severe, and may develop slowly over time. In the early stages of endocarditis, the symptoms are similar to many other diseases.
This is the reason why many cases are not diagnosed. Many of the symptoms are similar to cases of influenza or general infections, such as pneumonia.
However, some people experience severe symptoms that appear suddenly. These symptoms may be due to inflammation or the damage it causes.
The most common symptoms include:
- Pale skin.
- Night sweats.
- Muscle pain.
- Pain in the joints.
- Decreased appetite.
Severe signs and symptoms include:
- Blood in the urine.
- Swollen feet.
- Swollen legs
- Stomach swollen.
- Difficulty breathing.
- Enlarged spleen, which may be tender to the touch.
- Heart murmur, which is an unusual heartbeat.
Changes in the skin can also occur, including:
Red or purple spots on or under the fingers or toes.
Broken blood vessels that appear as red spots and are usually in the whites of the eyes, on the inside of the cheeks, on the roof of the mouth or on the chest.
The signs and symptoms of endocarditis vary widely from person to person. They can change over time, and depend on the cause of your infection.
If you have a history of heart problems, cardiac surgery or endocarditis, you should contact your doctor immediately if you have any of these symptoms, especially if you have a fever that has lasted more than three days or if you are unusually tired.
If the endocarditis is caused by bacteria, it will be treated with antibiotics. Your doctor will advise you to take these medications until the infection and inflammation go away.
This normally takes six weeks. If the infection is advanced, you can receive these antibiotics intravenously in a hospital until you show signs of improvement.
Damaged heart valves caused by endocarditis may require surgery to correct. Surgery can be done to remove the damaged heart valves and replace them with artificial valves.
If you have a milder case, the damaged area of your valve can be removed and replaced by surgical material or animal tissue.
What are the complications associated with endocarditis?
Complications can develop from the damage caused by your infection. These may include an abnormal heart rhythm such as atrial fibrillation, blood clots and jaundice.
This damage can not be limited to your heart, where endocarditis can result in damaged heart valves. Infected blood can also cause embolism, or clots, to travel to other parts of your body.
Other organs that may be affected are the following:
- In the kidneys, small vessels or glomeruli may become inflamed. This is called glomerulonephritis.
- Clots can travel to your lungs.
- Clots can travel to your brain and damage it.
- Your bones, particularly your spine, can become infected. This is called osteomyelitis.
Bacteria can escape from your heart and affect these areas. Bacteria can also cause abscesses in your organs or other parts of your body.
Some of the serious complications that can arise from endocarditis include stroke and heart failure.