Endocarditis is a rare and potentially fatal type of heart infection. It’s specifically an infection of the inner lining of the heart (the endocardium), most commonly caused by bacteria entering the blood and travelling to the heart.
The heart is well protected against infection and bacteria usually pass by without causing any harm. However, if the heart valves are damaged, or if a person has an artificial valve, it’s easier for bacteria to take root and bypass your normal immune response to infection.
Symptoms of endocarditis
The initial symptoms of endocarditis are similar to the flu and include:
- a high temperature (fever) of or above 38C (101.4F)
- joint and muscle pain
Left untreated the infection will damage the valves of the heart, disrupting the normal flow of blood through the heart.
This triggers a range of life-threatening complications, such as:
- heart failure – where the heart is unable to pump enough blood around the body to properly meet the body’s demands
- stroke – where the supply of blood to the brain becomes disrupted
What causes endocarditis?
Endocarditis is caused by a growth of bacteria on one of the heart valves, leading to an infected mass called a “vegetation”.
The infection may be introduced during brief periods of having bacteria in the bloodstream, such as after dental work, colonoscopy, and other similar procedures.
How is endocarditis diagnosed?
The infection on the valve can cause build up of nodules on the valves called “vegetations”. These valve vegetations can be detected by echocardiography (an ultrasound examination of the heart).
The most accurate method of detecting valve vegetations is with a procedure called transesophageal echocardiography (TEE). In this procedure an echo-transducer is placed on the tip of a flexible endoscope.
The endoscope is inserted through the mouth into the esophagus. The transducer at the tip of the endoscope is then able to take sound wave “pictures” of the heart valves located adjacent to the lower esophagus.
It is important to realize that endocarditis may exist without visible vegetations on the heart valve; the exact diagnosis is made by the identification of bacteria in a blood culture, in the appropriate clinical setting.
Endocarditis is treated with a course of antibiotics given via a drip. You will need to be admitted to hospital for this.
Around one in five people will also need surgery to repair or replace a damaged heart valve or drain away any abscesses that develop.
Endocarditis is a serious illness, especially if complications develop. Even with the highest standard of medical care the risk of dying is high – at around one in five. Early diagnosis and treatment is vital to improve the outlook for the condition.
Who is affected
You are more at risk of developing endocarditis if you:
- have a prosthetic (artificial) heart valve – valve replacement surgery is increasingly being used when people experience narrowing of one of their heart valves
- have congenital heart disease – congenital heart disease means a person is born with heart defects
- have damaged heart valves because of infection or heart disease
- inject drugs such as heroin – heroin users are three times more likely to develop endocarditis than the population at large
Even in these higher-risk groups, endocarditis remains a rare condition. In England, for example, endocarditis is estimated to affect around one in every 3,000 people in any given year.
Endocarditis is more common in older people, with half of all cases developing in people over 50. However, cases of endocarditis have been recorded in children, particularly those born with congenital heart disease.
Twice as many men are affected as women.
Although it may sound strange, rates of endocarditis are increasing because of advancements in medical care. This is because an increasing number of people are now being treated with valve replacement surgery or surgery to repair congenital heart disease.