What Is Endocarditis?

 

Endocarditis is a serious and potentially life-threatening condition characterized by inflammation of the inner lining of the heart’s chambers and valves—called the endocardium. This condition is often caused by a bacterial or fungal infection that enters the bloodstream and settles in the heart. When microorganisms invade the heart tissue, they can cause damage to the valves, disrupt normal heart function, and lead to dangerous complications if untreated.

Although rare in people with healthy hearts, endocarditis most commonly affects individuals with existing heart problems, artificial valves, or implanted cardiac devices. Early diagnosis and prompt medical treatment are critical to managing the disease effectively and preventing irreversible damage.

Common Symptoms

The symptoms of endocarditis can be subtle at first and may vary depending on the type and cause of the infection. The condition may develop over days or weeks (subacute) or strike suddenly (acute). Common symptoms include:

  • Fever and chills
  • Fatigue and weakness
  • Night sweats
  • Muscle or joint pain
  • Shortness of breath
  • Persistent cough
  • Unexplained weight loss
  • Pale skin or small red spots on the skin, eyes, or nails
  • Swelling in the legs or abdomen

Some people may also develop heart murmurs or worsening of existing murmurs as the infection damages the valves. In advanced cases, symptoms of heart failure may appear.

Causes of Endocarditis

Endocarditis is primarily caused by infection from bacteria, though fungi and other germs may also be responsible. These organisms enter the bloodstream through various means and travel to the heart.

Common Entry Points:

  • Dental procedures or poor oral hygiene
  • Skin wounds or infections
  • Catheter use (IV lines or urinary catheters)
  • Needle use, including IV drug use
  • Surgical procedures, especially involving the heart or lungs
  • Implanted medical devices (e.g., pacemakers, heart valves)

Normally, the immune system clears these microbes before they cause harm. However, if the inner heart lining is damaged or if a person is immunocompromised, these germs can colonize and grow on heart tissues or valves.

Who’s at Risk?

Several factors increase the risk of developing endocarditis, including:

  • Artificial heart valves: Prosthetic materials offer a surface for bacteria to adhere to.
  • Congenital heart defects: Structural abnormalities present from birth can attract pathogens.
  • History of endocarditis: Past infections increase the likelihood of recurrence.
  • Heart valve disease: Damaged valves are more prone to infection.
  • Implanted cardiac devices: Pacemakers and defibrillators are potential entry sites.
  • IV drug use: Non-sterile injections can introduce bacteria directly into the bloodstream.
  • Chronic conditions: Such as diabetes or cancer, which suppress the immune system.

People with poor dental hygiene, especially those with gum disease, are also at greater risk.

Types of Endocarditis

Endocarditis can be classified based on the type of organism involved and how quickly the disease progresses:

  • Acute Endocarditis: A sudden and severe infection that develops rapidly, often leading to serious damage within days.
  • Subacute (or Chronic) Endocarditis: Develops more slowly, with milder symptoms that worsen over time.
  • Infective Endocarditis: Caused by microbial infection (bacterial, fungal, or viral), and by far the most common type.
  • Non-infective Endocarditis: Rare, often linked to autoimmune diseases or cancer, without any identifiable pathogen.

How It's Diagnosed

Diagnosis begins with a review of medical history, physical exam, and blood tests. Your healthcare provider may look for a heart murmur or signs of infection. To confirm the diagnosis and pinpoint the organism, the following are commonly used:

Key Diagnostic Tools:

  • Blood cultures: To detect the presence of bacteria or fungi in the bloodstream.
  • Echocardiogram: An ultrasound of the heart that helps visualize vegetations (clumps of bacteria and cells) on valves.
    • Transesophageal echocardiogram (TEE) is more sensitive than the standard transthoracic method.
  • Electrocardiogram (ECG): Monitors heart rhythm and can detect changes caused by valve damage.
  • Chest X-ray or CT scan: May reveal heart enlargement or complications like embolisms.

In some cases, additional lab tests may be required to detect underlying immune responses or to evaluate organ function.

Treatment Options

Prompt medical intervention is essential for controlling the infection and preventing damage. The primary approach involves:

Antibiotic Therapy:

  • High-dose intravenous (IV) antibiotics are typically administered in a hospital setting for several weeks.
  • The antibiotic is chosen based on the identified organism and its sensitivity to medications.
  • Blood tests are regularly performed to monitor progress and adjust treatment if needed.

Antifungal Medications:

  • Used when fungi are the cause—typically more resistant and require longer treatment.

Surgical Intervention:

Some cases require surgery to repair or replace damaged heart valves, especially when:

  • The infection doesn’t respond to medication
  • There’s significant valve dysfunction
  • Heart failure symptoms worsen
  • There’s risk of embolism (clot or bacteria traveling to other organs)

Valve replacement may involve mechanical or biological prosthetics depending on patient-specific factors.

Possible Complications

If left untreated or diagnosed late, endocarditis can lead to severe complications, such as:

  • Heart failure: Caused by damaged valves or weakened heart muscle.
  • Stroke: Due to emboli traveling from the heart to the brain.
  • Pulmonary embolism: In right-sided endocarditis.
  • Kidney damage: From inflammation or blocked vessels.
  • Septicemia: A widespread bloodstream infection.
  • Abscesses: Localized infections in the heart or other organs.

Timely treatment reduces the likelihood of complications and improves outcomes significantly.

Preventive Measures

People at high risk can reduce their chances of developing endocarditis through a combination of lifestyle and medical strategies:

Prevention Tips:

  • Practice good oral hygiene: Brush and floss daily, and visit a dentist regularly.
  • Avoid unnecessary piercings or tattoos: These can introduce bacteria into the bloodstream.
  • Use sterile techniques for injections: Especially for individuals who require frequent IV access.
  • Take preventive antibiotics: Some individuals (e.g., those with prosthetic heart valves) may be prescribed antibiotics before certain dental or surgical procedures.
  • Manage chronic conditions: Keep blood sugar, cholesterol, and blood pressure under control.

If you've had endocarditis before or are at risk, speak to your doctor about personalized prevention protocols.

Living With Endocarditis

Recovery can take weeks or even months. Most patients need to continue follow-up care after discharge from the hospital, including:

  • Regular blood tests to ensure the infection is cleared
  • Imaging to monitor heart valve function
  • Cardiac rehabilitation for those who experienced complications
  • Ongoing antibiotic treatment at home (in some cases)

Emotional and mental health support may also be important, especially for individuals who faced a lengthy or traumatic experience.

FAQs About Endocarditis

Can endocarditis be cured?
Yes, with prompt treatment. Most people recover fully if diagnosed early.

Is endocarditis contagious?
No, but the germs causing it can be spread. Good hygiene is key.

Can you get endocarditis more than once?
Yes, recurrence is possible, especially without preventive care or if underlying heart conditions are present.

What is the prognosis?
With timely treatment, the survival rate is high. However, late diagnosis or complications can worsen outcomes.