Infective endocarditis is a serious infection of the endocardium (the smooth interior lining of the heart ) and/or the heart valves. Although several different types of organisms can cause endocarditis, it is usually caused by a bacterial infection. Endocarditis occurs when bacteria in the bloodstream "take up residence" and begin to grow and multiply on the heart valve. Contrary to what the name might suggest, "infective" endocarditis is not in fact contagious. There are four one-way heart valves that allow blood to be pumped forward from one chamber to another and throughout the body. At the same time these valves prevent blood from backing up into other chambers and the lungs.
Infective endocarditis may be acute or sub-acute. It can come on suddenly and become life-threatening within a matter of days, in which case it is called acute infective endocarditis. Subacute endocarditis usually develops gradually and subtly over a period of weeks to several months.
There are numerous ways that bacteria can get into the bloodstream to cause infection of the heart valve. Something as minor as a small cut can enable bacteria that normally live on the skin to get into the bloodstream. In some cases, this can occur during a dental procedure. In hospitalized patients, the IVs and catheters that are often inserted into the veins may be the portal through which bacteria get into the blood. For many endocarditis patients, however, no clear explanation is ever found regarding how the bacteria first got into the bloodstream.
The most common cause – a bacterial infection – may present in two ways:
As infection progresses, other symptoms may develop. If the infection begins to damage the heart valve, the valve may become "leaky." A leaky heart valve can eventually lead to blood backing up into the lungs. This accumulation of fluid in the lungs can cause shortness of breath. If the infection spreads to the kidneys, patients may notice blood in the urine. If the infection spreads to the brain, it can cause headaches, confusion, or even stroke.
Subacute bacterial endocarditis (SBE) has an insidious onset and may have some or all of all of the following symptoms:
In some 5 to 10% of cases, fungal infection or some rare bacteria may be the cause of endocarditis and in this group the blood cultures are negative.
Left untreated, this bacterial infection can gradually "eat away" at and damage the heart valve, causing it to malfunction. It is always fatal if untreated.
Possible complications include: Infected blood clots that may travel to the brain, kidneys, or abdominal organs causing infections, abscesses or stroke; heart-rhythm disturbances (atrial fibrillation is most common); destruction of heart valves; lung clots; arthritis; myositis (inflammation of muscles); acute renal failure.
Part of prevention is to maintain good oral hygiene.
Antibiotics are required for several weeks to fight infection. Antibiotic treatment is often intravenous.
If you have heart valve damage or a heart murmur, request antibiotics prior to medical procedures that may introduce bacteria into the blood. These include dental work, childbirth and surgery of the urinary or gastrointestinal tract.
Rest in bed until you are fully recovered. While in bed, flex your legs often to prevent clots from forming in deep veins. Resume your normal activities, including sexual relations when strength allows.