Heart valves allow one-way flow of blood through the heart. Damaged heart valves that do not open completely (called stenosis) or close completely (called regurgitation) are susceptible to infection because they cause abnormal blood flow through the valve. Infections of heart valves (known as endocarditis) are serious and can be life-threatening. The most common heart infections are caused by bacteria, though fungal infections can also occur. Prosthetic (replaced) or repaired heart valves are prone to infection. Growths of infectious tissue on heart valves are called vegetations and can lead to strokes due to pieces of tissue breaking off (called emboli) and blocking blood vessels in the brain. The March 28, 2007, issue of JAMA includes an article on infections of prosthetic heart valves.
Damaged or abnormal heart valves
Prosthetic heart valves
Intravenous illegal drug use causing heart valve damage from foreign substances and infectious agents injected into the bloodstream
Indwelling medical equipment such as intravascular catheters, pacemakers, and defibrillators serving as an entry point for bacteria
Fever
Back, joint, or muscle aches
Shortness of breath
Fatigue
Unusual rash or spots on skin
In addition to asking questions about your history and doing a physical examination, your doctor may order blood tests looking for anemia or an increased white blood cell count, which indicates infection. Blood may be sampled and cultured, looking for bacteria in the bloodstream. An echocardiogram (an ultrasound examination of the heart) can show abnormal blood flow through the heart or damage to the valves or heart chambers. Echocardiograms are also useful to diagnose serious complications of endocarditis, such as an abscess (a pocket of infection) and regurgitation.
Antibiotics are selected based on what type of bacteria or fungus grows in laboratory studies. Because heart valve infection is serious, treatment with intravenous antibiotics for a prolonged period of time (usually 4 to 6 weeks) may be necessary.
Surgery may be needed to repair or replace the damaged valve.
If you have an abnormal or prosthetic heart valve, your doctor may recommend antibiotic therapy before dental procedures or other invasive treatments to prevent bloodstream infections.
To find this and previous JAMA Patient Pages, go to the Patient Page Index on JAMA's Web site at http://www.jama.com. Many are available in English and Spanish. A Patient Page on endocarditis was published in the July 3, 2002, issue.
Sources: National Heart, Lung, and Blood Institute; American Heart Association; Centers for Disease Control and Prevention
The JAMA Patient Page is a public service of JAMA. The information and recommendations appearing on this page are appropriate in most instances, but they are not a substitute for medical diagnosis. For specific information concerning your personal medical condition, JAMA suggests that you consult your physician. This page may be photocopied noncommercially by physicians and other health care professionals to share with patients. To purchase bulk reprints, call 203/259-8724.
TOPIC: HEART DISEASE