Endocarditis, an inflammation of the inner wall of the heart, is quite rare: Around three in every 100,000 Western Europeans contract it every year. Some sufferers initially only experience harmless symptoms such as altered heart murmurs. Others suddenly develop a high fever.
It is particularly important for people who already suffer from heart problems that endocarditis is detected and treated at an early stage. Late treatment increases the risk of a fatal outcome.
Endocarditis is an infection of the inner lining of the heart, which primarily affects the heart valves. It often affects people who already have a pre-existing condition, for example because they have a heart malformation or heart disease. This is because bacteria can colonize the damaged heart more easily. They often enter the bloodstream via small injuries in the mouth and eventually attach themselves to the inner lining of the heart, the so-called endocardium. This smooth, thin layer of tissue lines the inside of the heart and separates the heart muscle from the cavity of the heart.
Men are affected by bacterial endocarditis twice as often as women. If your heart is already sick or under strain, you need to be particularly careful.
The likelihood of contracting bacterial endocarditis is increased in people with heart valve replacements, heart malformations and other heart diseases. Small injuries to the oral mucosa are enough to trigger the disease. Dental surgery, for example, creates minimal openings in the gums through which bacteria can enter the body. Irritation during tooth brushing can also lead to bleeding, which the germs then use as a gateway into the body.
Endocarditis is usually caused by bacteria. There are several types that can be responsible for endocarditis:
Fungi or other rare pathogens can also cause endocarditis.
In addition to infective endocarditis, there are other forms of endocarditis that arise from other causes. However, they are much rarer. These include:
In bacterial endocarditis, foci of inflammation form in the body – usually unnoticed. Initially there are no complaints. Nevertheless, these foci of inflammation can become dangerous as more and more bacteria accumulate there. They begin to detach over time, migrate through the body and attach themselves to the heart.
Depending on the pathogen, the infection on the inner wall of the heart may be more severe or milder. The body’s defense mechanisms also influence the course of the infection: the immune system usually works effectively enough to get rid of the bacteria quickly. Even if the germs reach the heart, they usually do not take hold and are eliminated by immune cells. However, minor injuries, for example after heart surgery, can be good starting points for bacteria.
Once the germs have established themselves, they damage the tissue and ultimately trigger endocarditis. The body is no longer able to renew the destroyed tissue. Particularly aggressive pathogens can cause major damage. More extensive defects therefore also occur more frequently in people with a weak immune system. The aortic valve and/or the mitral valve, which are heart valves on the left side of the heart, are often affected. The inflammation may lead to the heart valve being destroyed. It then becomes increasingly unable to fulfill its valve function and can no longer adequately regulate the blood flow. Problems sometimes also arise when deposits consisting of bacteria and inflammatory cells form on the heart valve.
Some sufferers have almost no symptoms, others have more severe symptoms. The heart murmurs often change or new ones appear within a few days. Most of those affected also have a more or less severe fever. Experts distinguish between the acute and subacute form of the disease, as both manifest themselves with different symptoms.
Subacute endocarditis is characterized by rather unspecific symptoms. Many sufferers notice that their body temperature rises slowly. However, it usually remains below 39 degrees, so that no severe fever develops.
Some sufferers also report other symptoms such as
As these symptoms are rather general, medical laypersons find them difficult to classify. For this reason, high-risk patients with heart disease in particular should have a medical examination.
This form is characterized by a rapid course of the disease. Those affected quickly have a fever of over 39 degrees, which can be accompanied by other symptoms. These include:
When you present to us with relevant complaints, we will first ask you about your symptoms and your previous illnesses – especially with regard to cardiovascular problems. This is followed by careful diagnostics. We use the following methods:
Early treatment is important, as bacterial endocarditis often leads to death if left untreated. It is therefore essential that you visit us if you have symptoms and a pre-existing heart condition.
Whether the disease progresses slowly or whether clearly noticeable symptoms appear quickly depends on the form of endocarditis. The acute form progresses rapidly, while the subacute form sets in more gradually. The prognosis depends on various factors. These include:
Complications can arise if bacteria deposited on the heart valves become detached and travel through the body via the bloodstream. There is then a risk of blockage of the blood vessels and embolisms with life-threatening blood clots. The possible consequences are
Blood clots are so dangerous because they can obstruct the blood supply to organs. If they constrict the blood vessels so much that the blood can no longer pass through properly, there is a risk of insufficient oxygen and nutrient supply – the brain, kidneys and spleen are frequently affected. If the cerebral artery is blocked, a stroke may be imminent. If it affects vessels in the kidney area, patients notice blood in their urine and complain of flank pain. If, on the other hand, abdominal pain occurs, it may be that the arteries that supply the intestines are blocked. Sometimes the failures only last for a short time, but sometimes the damage is so severe that it is difficult to recover.
Embolisms are occasionally also noticeable on the skin. Red nodules can form here, which are about the size of a lens and react sensitively to pressure. Sometimes small red dots also form on the skin and at the back of the eye. These are hemorrhages, the so-called petechiae.
If the bacteria have already damaged the heart valves, heart failure can develop. Possible symptoms of heart failure are
Other possible complications of endocarditis:
Patients at risk should be treated with an antibiotic as a preventive measure during operations in the mouth and throat area. You are a high-risk patient if you have a serious congenital heart defect, have previously had endocarditis, have had a valve replacement or reconstructed heart valves and have had a heart transplant with valve disease. As a high-risk patient, you should also take an antibiotic during dental treatment to prevent bacteria from causing damage that can enter the bloodstream via injuries in the oral cavity. Talk to your dentist about your pre-existing conditions and he or she will take appropriate measures.
People with a particularly high risk of endocarditis receive a personal endocarditis card. Further information at swissheart.ch
What you can do yourself: Make sure you maintain thorough oral hygiene to avoid periodontitis and prevent your gums from starting to bleed. Regular check-ups at the dentist also help to detect and treat possible dental diseases in good time, making surgery unnecessary. Also avoid tattoos.
We will be happy to advise you on which therapy is necessary. At the USZ, we treat endocarditis patients on an interdisciplinary basis, with the further treatment plan being determined in weekly meetings between specialists from cardiac surgery, infectiology and other specialist areas.
In the case of endocarditis, we usually prescribe four to six weeks of antibiotic therapy with an agent that exactly matches the pathogen. If you have received an artificial heart valve in the last twelve months and suffer from endocarditis, the new heart valve may also be affected. In this case, your chances of recovery increase if the artificial valve is replaced in addition to drug therapy. In the event of serious complications, surgical experts must remove the inflamed tissue. This procedure can prevent sepsis or progressive heart failure.