What is Endocarditis? What are the symptoms, types and prevention of Endocarditis, and how to diagnose and treat it?


Endocarditis is inflammation of the inner lining of the heart valves and chambers, which make up the endocardium. Usually, this inflammation is caused by a bacterial infection, which grows, giving rise to valvular vegetations, and rarely by a fungal infection.

This pathology is characterised by the accumulation of bacteria and clots in the valves that form vegetations and, when detached, can affect vital organs and cause death. Endocarditis is distinguished from inflammation of the heart muscle, called myocarditis, and inflammation of the membrane surrounding the heart, called pericarditis.

By sex, Endocarditis is three times more common in men than in women.


A viral or fungal infection can cause Endocarditis. Still, it is most commonly caused by the penetration of a small number of bacteria that reach the bloodstream through the oral cavity, skin, and respiratory tract. According to the Heart Foundation, the growth of microorganisms and the response of the immune system to control the infection can cause alterations in the function of the valve on which Endocarditis is based.

Among the risk factors that exist as a risk for contracting the disease are:

  • Any dental surgery procedure includes bleeding and gingivitis (infection and inflammation of the gums).
  •  Place permanent access lines (catheters) to the veins for intravenous drug use since bacteria are often injected directly into the vein through contaminated syringes or solutions.
  •  Respiratory tract procedures include tonsillectomy or bronchoscopy with a rigid bronchoscope, among others.
  •  Gastrointestinal tract procedures include biliary tract surgery or surgical operations involving the intestinal mucosa.
  • Genitourinary procedures, such as cystoscopies or vaginal delivery with infection.
  • Suffer from septicemia (infection of the blood)

It has been found that Endocarditis has a higher incidence among people with congenital defects of the heart chambers and valves, with artificial valves, or simply with an injury or malformation that allows blood to pass from one side of the heart to the other.


Symptoms can come on slowly (subacute) or suddenly (acute). In the case of acute bacterial Endocarditis, the first warning sign is a high fever (40ºC), accompanied by a rapid heart rate, fatigue and rapid valve damage. In addition, the infection can spread since, in some cases, emboli break off from the vegetation, and the kidneys and other organs can stop working (septic syndrome). If the blood vessels break, even death can occur.

Subacute Endocarditis is associated with mild fever (37.5-38.5ºC), weight loss, excessive sweating, anaemia, and skin spots similar to freckles (the result of haemorrhages caused by emboli) located on the palms of the hands. The nails, the feet soles, and the eyes’ whites (conjunctiva). The vagueness of these symptoms, which can last for months without a precise diagnosis, makes untreated subacute Endocarditis as dangerous a condition as acute Endocarditis.

Other symptoms observed in both types of Endocarditis are joint pain, chills, paleness, blood in the urine and difficulty breathing.


According to the American Heart Association, there is no way to prevent the onset of the disease. However, they maintain that people included in the risk groups can take preventive medications if they undergo some interventions detailed in Causes.

Included in the risk groups are those patients:

  • With congenital heart malformations.
  • heart transplants
  • Heart valve problems.
  • Artificial heart valves.
  • Previous history of infective Endocarditis.


The bacteria that usually cause the disease are streptococci and staphylococci. Depending on the aggressiveness of the bacteria, specialists distinguish between two types of Endocarditis:


Acute Endocarditis is caused by very aggressive germs and is characterised by the fact that it evolves over days or weeks.


Subacute Endocarditis is caused by a type of germs that are less virulent than those that cause the acute type. In this case, the course of the disease extends over weeks or months.


The specialist may suspect that a patient has Endocarditis when there is an infectious process with persistent fever without clear evidence of infection, mainly when it is associated with a heart murmur and/or the person has other cardiac symptoms.

The first step you have to take is to demonstrate the existence of microorganisms in the blood using blood culture and diagnose the vegetations, which will also help the professional to decide which treatment will be the most appropriate.

To confirm the diagnosis, the doctor may order an echocardiogram to identify the heart valves’ vegetation.


Initially recommended therapy will be the treatment of the infection with intravenous antibiotics. This may last several weeks.

In addition, the doctor must also treat the diseases and complications that arise from the disease, such as heart failure or stroke.

Surgery is only indicated in cases where the affected valve must be replaced by a prosthesis when the risk of embolism is very high or there are abscesses.


The prognosis of Endocarditis will depend on many factors, such as the size of the vegetation, the type of microorganisms that have caused the infection, the existence of embolisms or heart failure, and changes in the functioning of the affected valve.

This disease can become severe and cause death, even if the patient follows the treatment well.