Causes and Risks:

Endocarditis can involve the heart muscle, heart valves, or lining of the heart. Most people who develop endocarditis have underlying valvular heart disease. Injection drug use is a common risk factor for developing endocarditis.

Bacterial infection is the most common source of endocarditis. However, it can also be caused by viruses, fungi, or other microorganisms. In some cases, no causative organism can be identified.

Related topics:

• culture-negative endocarditis
• infective endocarditis

Prevention:

Preventive (prophylactic) antibiotics are often given to people with predisposing heart conditions before dental procedures or surgeries involving the respiratory, urinary, or intestinal tract. Continued medical follow-up is advised for people with a previous history of endocarditis.

Symptoms:

• fatigue
• weakness
• fever
• chills
• night sweats, may be severe
• weight loss
• muscle aches and pains
• heart murmur
• shortness of breath with activity
• swelling of feet, legs, abdomen
• blood in the urine
• sweating, excessive
• red skin spots, located on the palms and soles (called Janeway lesions)
• paleness
• nail abnormalities (splinter hemorrhages under the nails)
• joint pain
• abnormal urine color
• red, painful nodes in the pads of the fingers and toes (called Osler’s nodes)

Note: Endocarditis may develop symptoms slowly (subacute) or suddenly (acute).

Signs and Tests:

A history of congenital heart disease, intravenous drug use, or chronic localized abscess or infection, raises the index of suspicion. Physical examination may show an enlarged spleen (splenomegaly). The examiner may detect a new heart murmur, or a change in a previous heart murmur. Examination of the nails may show splinter hemorrhages. Eye examination may show retinal hemorrhages with a central area of clearing, called Roth’s spots, and petechiae (small pinpoint hemorrhages) may be detected in the conjunctiva. The fingertips may become enlarged and the nails may curve (clubbing).

Tests:

• repeated blood culture and sensitivity (#1 test for detection)
• ESR (erythrocyte sedimentation rate)
• CBC may show low grade, microcytic (small red blood cells) anemia
• echocardiogram
• transesophageal echocardiogram
• chest X-ray

Treatment:

Hospitalization is often required initially to treat administer intravenousantibiotics. Long-term high-dose antibiotic therapy is required to eradicate the bacteria from the heart chambers and vegetations on the valves. Therapy up to 6 weeks is not uncommon. The chosen antibiotic must be specific for the organism causing the condition. This is determined by the blood culture and the sensitivity tests.

Activity is restricted to bed rest initially, then it is gradually increased as the condition improves. No special diet (such as a low-salt diet) is necessary, unless it is required because of an underlying heart disorder.

If heart failure develops as a result of damaged heart valves, surgery to replace the affected heart valve may be indicated.

Prognosis:

Early treatment of endocarditis improves the chances of a good outcome.

Complications:

• congestive heart failure if treatment is delayed
• blood clots or emboli that travel to brain, kidneys, lungs, or abdomen, causing severe damage to these organs
• arrhythmias (rapid or irregular heartbeat), such as atrial fibrillation
• glomerulonephritis
• severe heart valve damage
• stroke
• brain abscess
• brain or nervous system changes
• jaundice

Call your health care provider if you note the following symptoms during or after treatment:

• weight loss without change in diet
• blood in urine
• chest pain
• weakness
• fatigue
• numbness
• fever