Endocarditis is an infection in the endocardium (the inner lining of the heart muscle, which also covers the heart valves) in which the endocardium becomes damaged and bacteria stick to the heart valves or heart lining. The endocardium lines all four chambers of the heart which blood passes through as the heart beats. It also covers the four valves, which normally open and close toallow the blood to flow in only one direction through the heart during each contraction. For the heart to pump blood efficiently, the four chambers must contract and relax, and the four valves must open and close, in a well coordinated fashion. Endocarditis can interfere with the heart's ability to do its job. The endocardium can be damaged and made more susceptible to infection byheart defects that are present at birth, such as mitral valve prolapse, in which blood leaks through a poorly functioning mitral valve back into the heart; scarring of the heart muscle, such as rheumatic fever; or replacement of a heart valve. Bacteria can get into the blood stream (a condition knownas bacteremia) in many ways: by spreading from a local infection such as a urinary tract infection, pneumonia, or skin infection; as a result of certainmedical conditions, such as severe periodontal disease, colon cancer, or inflammatory bowel disease; during minor surgery, such as periodontal surgery, tooth extractions, teeth cleaning, tonsil removal, prostate removal, orendoscopic examination; and through catheters used for intravenous medications and feeding, or dialysis. In people who use intravenous drugs, the bacteriacan enter the blood stream through unsterilized, contaminated needles and syringes.
If not discovered and treated, infective endocarditis can permanently damagethe heart muscle, especially the valves. It can lead to heart failure, a chronic condition in which the heart is unable to pump blood well enough to adequately supply the body. The vegetation formed by bacteria colonizing on heartvalves may break off and form emboli, which can travel through the circulation, get stuck in blood vessels, and block blood flow. This can damage tissues, and affect the brain or the kidneys. Most cases of infective endocarditis occur in people between the ages of 15-60. Men are affected about twiceas often as women. The most common symptom of endocarditis is a mild fever. Other symptoms include chills, weakness, cough, trouble breathing, headaches,aching joints, and loss of appetite. Emboli may also cause Osler's nodes (small, reddish, painful bumps usually found on the inside of fingers and toes);petechiae (tiny purple or red spots on the skin); tiny hemorrhages resemblingsplinters under the fingernails or toenails; coughing; shortness of breath;symptoms of a mini-stroke (numbness, weakness, or paralysis on one side of the body or sudden vision loss or double vision); kidney damage; or an enlargedspleen. Anyone experiencing any of these symptoms should seek medical help immediately.
Doctors diagnosis endocarditis through a medical history, a physical examination, a blood test, and usually echocardiography. When doctors suspect infective endocarditis, they admit the patient to a hospital and treat the infectionwith antibiotics. In recent years, it has become harder to treat endocarditis because of people's resistance to antibiotics. Doctors may need to try a few different types of antibiotics-or even a combination of antibiotics--to successfully treat the infection. Antibiotics are usually given for aboutone month, but may need to be given longer if the infection is resistant totreatment. Once the fever and the worst of the symptoms have gone away, the patient may be able to continue antibiotic therapy at home but should regularly visit his/her doctor to make sure that the antibiotic therapy is working and is not causing adverse side effects, and that there are no complications. The patient should immediately tell the doctor about any symptoms that could indicate serious complications: trouble breathing or swelling in the legs, headache, joint pain, blood in the urine, or stroke symptoms, fever, chills, diarrhea, rash, itching. In cases of heart failure, recurring emboli, infection that doesn't respond to treatment, poorly functioning heart valves, and endocarditis involving prosthetic (artificial) valves, the most common surgical treatment cuts away (debriding) damaged tissue and replacing the damagedvalve.
If left untreated, infective endocarditis continues to progress and is alwaysfatal. If it is diagnosed and properly treated within the first six weeks ofinfection, it can be completely cured in about 90% of cases. The outcome depends on the patient's age and overall physical condition, the severity of thedisease involved, the exact site of the infection, how well the antibioticswork, and what kind of complications the endocarditis may be causing. Peoplewho are prone to endocarditis should tell health-care professionals before any surgical or dental procedures. They must be treated with antibiotics beforethese procedures to minimize the risk of infection.