Endocarditis is an inflammation of the inner lining of the heart, endocardium, caused by infection. The infection is from microorganisms that enter the blood stream and come to the heart this way. Beside the infection, there is an inflammation, especially of the heart valves, where the bacteria start to accumulate and blood clots form. The heart valves are susceptible to infections, especially if damaged or replaced.

Infectious endocarditis is mostly a chronic disease that develops in weeks or months. In rare cases, endocarditis is acute that can damage one or more heart valves in a short time. Acute endocarditis may bring to acute heart failure in a few days, which can be life-threatening.

Generally, endocarditis is not common in people with healthy hearts, but in people with damaged heart valves, heart defects or artificial heart valves.



The most common causes of endocarditis are bacteria, and fungi, in rare cases. Harmless microorganisms may enter the blood flow during dental procedures, especially when a tooth is taken out or a surgery of the digestive or urinary tracts. Another cause could be inserted catheter in the bladder or long-term treatment when intravenous catheter has to be placed.

The cause of endocarditis during surgery, for e.g., replacement of heart valves is rare.

If you are healthy, these germs may even be destroyed by your immune system. With damaged valves, the endocardium is a good place for them to accumulate.



The symptoms of infectious endocarditis may be as symptoms for other diseases and may not be heart-related or to the damage of the heart. These are:

  • excessive fatigue
  • higher body temperature and night sweating
  • joint pain
  • loss of weight

The infected material from the valve may cut and block any blood vessel in the body. Small blood clots may for e.g. block a vein under the fingernails, causing small hemorrhaging, similar when you see a thorn in the nail. If the clot clogs an artery supplying the brain with blood, a stroke may occur.

The symptoms of acute endocarditis are sudden. These are:

  • high temperature
  • heart palpitations (discomforting feeling when the heart beats irregularly or rapidly)

These symptoms may get worse very fast. If it comes to acute heart failure, other symptoms may occur, such as shortness of breath and hissing sound from the lungs.


Risk Factors

The risk of developing infectious endocarditis is high in:

  • people with heart problems like, damaged valves, artificial valves
  • persons with weakened immune system, such as in persons with HIV or cancer patients
  • drug addicts, intravenously taking drugs, especially sharing a needle



Endocarditis may cause the following complications:

  • Heart failure
  • Stroke
  • Damage other organs (lungs, abdominal organs, kidneys, extremities)
  • Infections in other parts of the body