What is endocarditis?

Endocarditis is a serious infection of one of the four heart valves.

What causes endocarditis?

Endocarditis is caused by a growth of bacteria on one of the heart valves, leading to an infected mass called a "vegetation". The infection may be introduced during brief periods of having bacteria in the bloodstream, such as after dental work, colonoscopy, and other similar procedures.

What are the symptoms of endocarditis?

Patients with endocarditis can develop:

• fever,
  
  
• fatigue,
  
  
• chills,
  
  
• weakness
  
  
• aching joints and muscles,
  
  
• night sweats,
  
  
• edema (fluid collection) in the leg(s), foot (feet), and abdomen,
  
  
• malaise,
  
  
• shortness of breath, and
  
  
• occasionally, scattered small skin lesions.

Who is at risk for endocarditis?

People with existing diseases of the heart valves (aortic stenosis, mitral stenosis, mitral regurgitation, etc.) and people who have undergone heart valve replacements are at an increased risk of developing endocarditis. These people are usually given antibiotics prior to any procedure which may introduce bacteria into the bloodstream. This includes routine dental work, minor surgery, and procedures that may traumatize body tissues such as colonoscopy and gynecologic or urologic examinations. Examples of antibiotics used include oral amoxicillin (Amoxil) and erythromycin (Emycin, Eryc,PCE), as well as intramuscular or intravenous ampicillin, gentamicin, and vancomycin.

How is endocarditis diagnosed?

The infection on the valve can cause build up of nodules on the valves called "vegetations". These valve vegetations can be detected by echocardiography (an ultrasound examination of the heart). The most accurate method of detecting valve vegetations is with a procedure called transesophageal echocardiography (TEE). In this procedure an echo-transducer is placed on the tip of a flexible endoscope. The endoscope is inserted through the mouth into the esophagus. The transducer at the tip of the endoscope is then able to take sound wave "pictures" of the heart valves located adjacent to the lower esophagus. It is important to realize that endocarditis may exist without visible vegetations on the heart valve; the exact diagnosis is made by the identification of bacteria in a blood culture, in the appropriate clinical setting.

How is endocarditis treated?

The mainstay of treatment is aggressive antibiotics, generally given intravenously, usually for 4-6 weeks. The duration and intensity of treatment depends on the severity of the infection and the type of bacterial organism responsible. In cases where the valve has been severely damaged by the infection, resulting in severe valve dysfunction, surgical replacement of the valve may be necessary. Response to treatment is indicated by a reduction in fever, negative blood bacterial cultures, and findings on echocardiography.