Infective Endocarditis
A serious infection of the heart valves and inner lining
Quick Facts
- Type: Heart infection
- Cause: Bacteria (or fungi) in the bloodstream
- Often affects: Heart valves
- Urgency: Serious — needs prompt hospital treatment
Overview
Infective endocarditis is an infection of the endocardium, the inner lining of the heart chambers and valves. It usually develops when bacteria, or less often fungi, enter the bloodstream and attach to a heart valve or damaged area of the heart. There they form clumps of infected tissue, called vegetations, that can damage the valve and break off to travel elsewhere in the body.
It is an uncommon but serious condition that can be life-threatening if not treated. People with abnormal or artificial heart valves and other heart conditions are at higher risk. Treatment usually requires a prolonged course of antibiotics in the hospital, and sometimes surgery, so early recognition is important.
Symptoms
Symptoms can develop gradually over weeks or come on more quickly, and they may be vague at first. Common signs include:
- Fever, chills, and night sweats
- Fatigue and a general feeling of being unwell
- Aching muscles and joints
- A new or changed heart murmur
- Shortness of breath
- Unexplained weight loss
- Small skin spots, tiny areas of bleeding under the nails, or painful nodules on the fingers or toes
Endocarditis can lead to serious complications such as stroke or organ damage if pieces of infected tissue travel in the blood. Seek urgent care for a persistent unexplained fever, especially with a known heart condition, and emergency care for sudden weakness, trouble speaking, or severe breathlessness.
Causes
Infective endocarditis develops when germs enter the bloodstream and settle on heart tissue. Ways bacteria can enter the blood include:
- Dental or medical procedures: That allow bacteria from the mouth or body to enter the blood.
- Infections elsewhere: Such as skin, gum, or other infections that spread to the blood.
- Injection drug use: Using non-sterile needles can introduce germs directly.
- Intravenous lines and catheters: Long-term devices can be an entry point.
- Poor dental hygiene: Which increases bacteria in the mouth.
The germs are more likely to take hold on valves that are already abnormal, artificial, or previously infected.
Risk Factors
- Artificial (prosthetic) heart valves
- A previous episode of endocarditis
- Certain congenital heart conditions
- Damaged heart valves, for example from rheumatic fever
- Injection drug use
- Long-term intravenous catheters
- Poor dental health
Diagnosis
Diagnosis combines the clinical picture with blood tests and heart imaging.
- Blood cultures: Several blood samples are taken to identify the responsible germ and guide antibiotics.
- Echocardiogram: An ultrasound of the heart that can show vegetations and valve damage; a more detailed scan through the esophagus is often used.
- Blood tests: To look for signs of infection and assess organ function.
- Additional imaging: Sometimes used to look for spread of infection to other organs.
Treatment
Infective endocarditis requires prompt, intensive treatment, usually in the hospital.
- Intravenous antibiotics: A prolonged course, often several weeks, targeted at the specific germ found in blood cultures. This is the cornerstone of treatment.
- Antifungal medicines: When a fungal infection is responsible.
- Surgery: May be needed to repair or replace a badly damaged valve, remove infected tissue, or treat complications.
- Monitoring and supportive care: For heart function and complications such as stroke or kidney problems.
Close follow-up is important even after treatment, because the infection can recur.
Prevention
- Maintain good dental hygiene and have regular dental check-ups
- Care promptly for skin and other infections
- If you are at high risk, ask your clinician whether preventive antibiotics are recommended before certain dental or medical procedures
- Avoid injection drug use, and never share needles
- Tell all healthcare providers about any heart valve condition
When to See a Doctor
See a clinician promptly for an unexplained fever lasting more than a few days, especially if you have an artificial valve, a known heart condition, or a previous episode of endocarditis. Seek emergency care for sudden weakness, numbness, trouble speaking, severe shortness of breath, or chest pain, which could signal a serious complication such as a stroke or heart failure.
Frequently Asked Questions
What is infective endocarditis?
It is an infection of the inner lining of the heart and its valves, usually caused by bacteria that enter the bloodstream and settle on heart tissue. The infection can damage valves and send infected fragments to other parts of the body, making it serious.
Who is at risk for endocarditis?
People at higher risk include those with artificial heart valves, a previous episode of endocarditis, certain congenital heart conditions, damaged valves, long-term intravenous catheters, and those who inject drugs. Poor dental health also increases the risk.
How is infective endocarditis treated?
Treatment usually involves a prolonged course of intravenous antibiotics in the hospital, targeted at the specific germ identified in blood cultures. Some people also need surgery to repair or replace a damaged valve or remove infected tissue.
Can endocarditis be prevented?
Good dental hygiene, prompt treatment of infections, and avoiding injection drug use all help. People at high risk may be advised to take preventive antibiotics before certain dental or medical procedures, so ask your clinician what applies to you.
When should I worry about a fever with a heart condition?
If you have an artificial valve, a known heart valve problem, or a prior episode of endocarditis, an unexplained fever lasting more than a few days should be checked promptly. Seek emergency care for sudden weakness, trouble speaking, or severe breathlessness.
References
- American Heart Association. Infective Endocarditis.
- MedlinePlus, U.S. National Library of Medicine. Endocarditis.
- Mayo Clinic. Endocarditis — Symptoms and causes.
- Centers for Disease Control and Prevention (CDC). Endocarditis.