Infective endocarditis is a disease that affects the heart. Specifically, it is an inflammation of the endocardium, a thin membrane that lines the inside of the heart chambers and forms the heart valves. This condition is caused by infection with microorganisms, mainly bacteria (less frequently fungal infections), which enter the bloodstream and adhere to the endocardium, forming vegetations. If not treated properly, infective endocarditis can have serious health consequences, including potentially life-threatening complications.
Symptoms of endocarditis
Infective endocarditis can present with a wide variety of symptoms, which can vary in intensity and duration depending on factors such as the microorganism causing the infection, the patient’s overall health, and whether the endocarditis is acute or subacute.
Common symptoms:
Fever: is the most frequent symptom, present in most cases.
Fatigue and generalized weakness: due to the infection and cardiac involvement.
New or changed heart murmur: the presence of vegetations can alter blood flow, causing murmurs.
Night sweats: related to fever and the inflammatory response.
Unexplained weight loss: due to the febrile state and increased metabolism.
Less common symptoms:
Petechiae: small red spots on the skin or mucous membranes.
Janeway lesions: painless lesions on the palms of the hands or soles of the feet.
Osler nodes: painful lesions on the fingertips.
Retinal hemorrhages: they can be observed during an eye exam.
Stroke: due to cerebral emboli.
Variation of symptoms according to the type of endocarditis:
Acute endocarditis: symptoms usually appear suddenly and are more intense. High fever, chills, and general malaise are common.
Subacute endocarditis: the symptoms develop gradually over weeks or months and may be more subtle. Fatigue, low-grade fever, weight loss, and night sweats are common.
It is important to note that some people with infectious endocarditis may not present any symptoms, especially in the early stages of the disease. Therefore, it is crucial to seek medical attention if endocarditis is suspected, even if the symptoms are mild.
Classification of endocarditis
The classification of endocarditis is based on several factors, including the cause of the infection, the speed of onset of symptoms, and the heart valves affected.
According to the cause:
Infectious: caused by bacteria (the most common), fungi or, rarely, other microorganisms.
Bacterial: it can be caused by a variety of bacteria, including Staphylococcus aureus, Streptococcus viridans, Enterococcus, and others.
Fungal: less common, but more serious, it often affects people with weakened immune systems or who have received antibiotics for long periods. Candida is a common fungus that causes endocarditis.
Device-associated endocarditis: related to prosthetic valves or implantable cardiac devices.
Non-infectious (or marantic): caused by sterile blood clots (thrombi) that form in damaged or artificial heart valves. It is also known as non-bacterial thrombotic endocarditis (NBTE). It can be a precursor to infectious endocarditis if bacteria colonize the thrombi.
According to the speed of onset:
Acute: the symptoms appear suddenly and progress rapidly, often within days. It is usually caused by more aggressive bacteria, such as Staphylococcus aureus.
Subacute: the symptoms develop gradually over weeks or even months. It is often caused by less aggressive bacteria, such as Streptococcus viridans.
According to the affected valve:
Mitral valve: it affects the valve that separates the left atrium from the left ventricle.
Aortic valve: it affects the valve that separates the left ventricle from the aorta.
Tricuspid valve: it affects the valve that separates the right atrium from the right ventricle.
Pulmonary valve: it affects the valve that separates the right ventricle from the pulmonary artery.
Prosthetic-device endocarditis: it affects artificial heart valves (mechanical or biological).
Right-sided endocarditis: It affects the tricuspid and pulmonary valves and is more common in intravenous drug users.
Causes of endocarditis
Infective endocarditis occurs when bacteria or fungi enter the bloodstream and attach to the endocardium, especially in damaged areas or on artificial heart valves. These bacteria can come from different sources, such as infections in other parts of the body (skin, mouth, urinary tract), medical or dental procedures, or intravenous drug use.
Non-infective endocarditis is often associated with conditions that increase blood clotting, such as certain types of cancer, autoimmune diseases, or trauma.
It is essential to seek medical advice if endocarditis is suspected, as complications can be serious and potentially life-threatening.
Diagnosis of endocarditis
The diagnosis of endocarditis involves a complete medical evaluation, which includes:
Medical history and physical examination: the doctor will review the patient’s symptoms, medical history, and risk factors. During the physical exam, the doctor will listen to the heart with a stethoscope to detect heart murmurs, which are abnormal sounds caused by turbulent blood flow. The doctor will also look for other signs of infection, such as fever, chills, petechiae (small red spots on the skin), and Osler’s nodes (painful nodules on the fingers or toes).
Blood cultures: this is the most important test for diagnosing infectious endocarditis. Several blood samples are drawn from different veins at different times to maximize the likelihood of isolating the microorganism causing the infection. Positive blood cultures, which show bacterial or fungal growth, confirm the diagnosis of infective endocarditis and allow identification of the specific microorganism, which guides the choice of the most appropriate antibiotic treatment.
Biomarkers of inflammation: blood tests are performed to measure markers of inflammation, such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and white blood cell count. Although these markers are often elevated in endocarditis, they are not specific to this disease and may be increased in other inflammatory conditions.
Echocardiography: this imaging test uses sound waves to create images of the heart and heart valves, allowing for the visualization of vegetations (accumulations of bacteria, blood clots, and cells), abscesses, valve perforations, and other abnormalities. There are two main types of echocardiograms: transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE). TTE is a non-invasive test performed by placing a transducer on the patient’s chest. It provides an overview of the structure and function of the heart, but may have limitations in visualizing certain areas, especially in obese patients or those with lung disease. TEE, on the other hand, is a more invasive test that involves inserting a transducer through the esophagus. It provides higher-quality, higher-resolution images than TTE, allowing better visualization of heart valves, vegetations, and abscesses. At HM Hospitales, we have the most advanced echocardiography technology, including 3D TEE, for accurate diagnosis.
Cardiac computerized tomography (CT): it can be useful for assessing the extent of the infection in surrounding structures, such as the pericardium (the membrane surrounding the heart) and large blood vessels. It can also detect septic emboli (infected blood clots that have traveled to other parts of the body).
Cardiac magnetic resonance imaging (MRI): it provides detailed images of the heart and heart valves, and can be useful for detecting complications such as myocardial abscesses (abscesses in the heart muscle) and mycotic aneurysms (abnormal dilations of the arteries caused by infection).
Treatment of endocarditis
The treatment of endocarditis depends on the type and severity of the infection, as well as the patient’s overall health.
Infective endocarditis
The treatment of infective endocarditis focuses on eliminating the infection and preventing complications. The main focus is antibiotic therapy, often combined with surgery in severe cases. The duration and type of treatment depend on several factors, including the microorganism causing the infection, the severity of the condition, the presence of complications, and the patient’s overall health.
Intravenous antibiotics: they are administered over a prolonged period, usually 4 to 6 weeks. The specific choice of antibiotics depends on the microorganism causing the infection and the presence of drug allergies. In some cases, antifungal medications may also be used if the infection is caused by fungi.
Other medications: these are used to treat the symptoms and complications of endocarditis, such as medications for fever, pain, or heart failure.
Surgery: cardiac surgery is considered in cases of heart failure, large vegetations with risk of embolization, abscesses or antibiotic-resistant infections, as well as in fungal endocarditis. Surgery may involve repairing or replacing the affected valve, draining abscesses, or debriding infected tissue. Valve prostheses can be mechanical (requiring lifelong anticoagulation) or biological.
Post-operative care: post-operative care is essential for proper recovery, including respiratory physiotherapy, pain management, and anticoagulation control.
Non-infective endocarditis
In non-infective endocarditis, treatment focuses on preventing new clots and addressing the underlying cause, using anticoagulants (warfarin, heparin, rivaroxaban, apixaban, dabigatran), antiplatelet agents (aspirin, clopidogrel), and specific treatment of the underlying disease. The duration of anticoagulant treatment is adjusted to the individual risk of thromboembolism.
At HM Hospitales, we have multidisciplinary teams to provide comprehensive and personalized cardiology care.
Remember that this article is for informational purposes only and does not replace professional medical advice. If you suspect you have complications and symptoms related to endocarditis, consult a specialist to obtain an accurate diagnosis and an appropriate treatment plan tailored to your needs. as relacionados con la endocarditis, consulta con un especialista para obtener un diagnóstico preciso y un plan de tratamiento adecuado a tus necesidades.
Our doctors
Contact and make an appointment with the professionals in this area
