Infective Endocarditis

What is infective endocarditis?

Infective endocarditis is an infection of the inner lining of the heart and the heart valves with bacteria or, less commonly, a fungus. People at risk of this condition are people who have had a procedure involving their blood vessels, people who have had heart valve problems in the past, and people who use IV drugs. Symptoms can be unspecific, and include fever, weakness, a loss of appetite, sweating, shortness of breath and swelling of the feet. Diagnosis is sometimes difficult and has to fulfill certain criteria, such as evidence of the bug causing the infection in several blood samples. Intravenous antibiotic treatment (through a drip) over several weeks is needed to completely treat the infection. Even with appropriate treatment this condition can be life-threatening.

Risks

Bacteria or fungi can enter the bloodstream through small injuries (such as during the cleaning of the teeth), when injecting into the veins, during surgeries, or during other infections. If bacteria or fungi reach the heart, they may can settle on the endocardium (the inner lining of the heart or the heart valves), and begin to grow, causing an infection. The infection causes swelling, scarring and damage to the heart lining and valves. Heart valves that are already damaged and artificial heart valves provide a good environment for these infections, and people with these conditions are at especial risk of developing infective endocarditis. Other risk factors include intravenous drug use, having device in place to keep a vein open, or undergoing another procedure that requires accessing the veins. This condition can affect people of all ages, but most commonly affects younger adults.

Symptoms

The symptoms of infective endocarditis may begin slowly and be vague in the early stages. General symptoms include nausea, a fast pulse, a feeling of weakness, weight loss, sweating and joint pain. People with infective endocarditis may have a fever that comes and goes. Small red spots under the nails, on the palms or the soles may be visible. Other symptoms may occur if organs are damaged, and this is may be different from person to person. Some people may develop a cough, become slowly more short of breath, or develop swelling of the feet and legs.

Diagnosis

Diagnosis is based on the symptoms, physical examination and certain diagnostic tests. Making the diagnosis can be difficult and has to fulfill specific criteria. These tests include blood tests to try and identify the cause of the infection. An ultrasound of the heart may show a growth on the heart valve, and any damage to the valves. Further diagnostic tests can be done to investigate for involvement of other organs.

Treatment

Treatment involves intravenous (through a drip) antibiotics over several weeks. If there is damage to the heart valves, surgical replacement of the damaged valves may be necessary.

Prevention

Using sterile techniques when injecting into the veins is important to prevent bacteria and fungi from entering the bloodstream. This may involve maintaining high standards of hygiene in the hospital setting and treating infections helps to prevent endocarditis. People who have a high risk of infective endocarditis may need to take antibiotics in certain situations to prevent developing this condition.

Other names for infective endocarditis

  • Bacterial endocarditis
  • Heart valve infection
  • Infectious endocarditis