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Infective endocarditis Causes and Risks:
Infectious endocarditis may involve the heart muscle , heart valves, or lining of the heart. Most people who develop infectious endocarditis have underlying heart disease . Sources of the infection may be transient bacteremia , which is common during dental, upper respiratory , urologic, and lower gastrointestinal diagnostic and surgical procedures. The infection causes growths on the heart valves, the lining of the heart, or the lining of the blood vessels. These growths may be dislodged and send clots to the brain, lungs, kidneys, or spleen. The incidence is 5 out of 100,000 people.
Many bacteria can cause endocarditis but a common mouth organism, Streptococcus viridans, is responsible for approximately half of all bacterial endocarditis. Other common organisms include staphylococcus and group D streptococcus. Less common organisms include Pseudomonas, Serratia, Candida, and many others.
Endocarditis may develop symptoms slowly (subacute) or suddenly ( acute ). Fever is a hallmark of both. In the slower form, fever may be present on a daily basis for months before other symptoms appear. Other symptoms are nonspecific such as fatigue , malaise (general discomfort), headache , and night sweats. As the illness progresses, small dark lines, called splinter hemorrhages , may appear under the fingernails. The health care provider may hear changing murmurs and detect an enlarged spleen and mild anemia . Murmurs are caused when clumps of bacteria, fibrin and cellular debris, called vegetations, collect on the heart valves. The mitral valve is the most common valve affected, followed by the aortic valve.
Preexisting conditions that increase the likelihood of developing endocarditis include: Since Streptococcus viridans is a common mouth organism and the most common cause of bacterial endocarditis, dental procedures can put children with congenital heart conditions at risk for endocarditis. It is common practice for children with some forms of congenital heart disease to start on antibiotics prior to any dental procedures.
Prevention:
Preventive (prophylactic) antibiotics are often given to people with predisposing congenital or valvular abnormalities 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 infective endocarditis.
Symptoms:
Signs and Tests:
A history of congenital heart disease 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.
Tests:
Treatment:
Hospitalization is required initially to administer intravenous antibiotics. 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 sensitivities tests.
Activity is restricted to bed rest initially, then it is gradually increased as the condition improves. No special diet is necessary, unless it is required because of an underlying heart disorder (such as a low-salt diet).
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 bacterial endocarditis generally results in a good outcome. Valvular damage may be present if diagnosis and treatment are delayed.
Complications:
Call Your Healthcare Provider:
Call your health care provider if you note the following symptoms during or after treatment:
This is a cross-sectional view of the interior of the heart. The valves, chambers, and associated vessels are labeled.
This is an illustration of the exterior of the heart. The arteries are colored blue and represent blood that is flowing into the heart. The veins are red and indicate blood flow out from the heart. The chambers are also labeled.
Osler's nodes are tender, raised, red (erythematous) bumps in the pads of the finger. They result when bacteria from an infected heart lining or infected heart valves lodge in the finger pads. This picture shows an Osler's node on the index finger in the middle of the image.
Janeway lesions are seen in people with acute bacterial endocarditis. They appear as flat, painless, red to bluish-red spots on the palms and soles.
This individual has Tetrology of Fallot, a type of heart disease present from birth (congenital) that causes the skin to appear bluish (cyanosis). This photograph shows both cyanosis, and broadening of the fingertips with loss of the angle between the nail and quick and rounding of the nail (clubbing). Diseases which result in decreased oxygen in the blood often have associated clubbing.
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