Myocarditis and Pericarditis

Myocarditis and pericarditis are inflammatory conditions that affect the heart. Myocarditis is inflammation of the myocardium, which is the heart muscle. Pericarditis is inflammation of the pericardium, the sac-like tissue layer that surrounds the heart.

Typical symptoms of myocarditis include chest pain and sometimes fever. More rarely, children may experience palpitations, dizziness, or lightheadedness, or may pass out.

Most cases of myocarditis in children are caused by viral infection. Other causes of myocarditis can include:

• Bacterial infections such as Lyme disease
• Autoimmune diseases
• Hypersensitivity reactions to medications
• Toxic reactions to drugs
• Vaccinations (including rare cases after COVID-19 vaccination)

Myocarditis is diagnosed through a complete medical history and physical examination, as well as tests to specifically evaluate heart abnormalities, including:

• Electrocardiogram
• Chest X-ray
• Blood tests, including evaluation of heart enzymes (such as troponin)
• Echocardiogram (cardiac ultrasound)

Treatment depends on the cause and severity of myocarditis. Children with myocarditis are admitted to the hospital so they can be monitored for arrhythmias. In many cases, treatment is supportive and the heart muscle inflammation improves on its own with time. In other cases, children may receive anti-inflammatory medications to decrease heart muscle inflammation more rapidly.

Typical symptoms of pericarditis include fever and chest pain that is often sudden and short-lived. The chest pain is often more severe when lying down and is less severe when sitting up and leaning forward.

When the pericardium is inflamed, it produces fluid. A large amount of fluid can compress the heart, limiting its ability to fill normally with blood. This can cause chest pain, tachycardia (rapid pulse rate), and hypotension (reduced blood pressure).

There are multiple causes for pericarditis including:

• Infections: including viral, bacterial (such as tuberculosis), fungal, and protozoal
• Postpericardiotomy syndrome (Dressler’s syndrome), which occurs in a small number of patients after heart surgery
• Rheumatologic diseases, including systemic lupus erythematosus, rheumatoid arthritis, and rheumatic fever
• Kawasaki disease
• Medications that can cause inflammation, such as hydralzaine and procainamide
• Kidney failure
• High-dose radiation associated with treatment of certain cancers, such as Hodgkin lymphoma

Pericarditis might be suspected if your child has chest pain or if the physician hears an abnormal heart sound called a “rub,” which occurs when the pericardium is irritated.

In addition to a complete medical history and physical examination, tests to diagnose pericarditis may include:

• Blood tests to evaluate the degree of inflammation
• Chest X-ray
• Echocardiogram (cardiac ultrasound)

Treatment depends on the cause of the inflammation and the amount of extra fluid in the chest. Many cases are mild and may improve with rest. Your child’s doctor may recommend over-the-counter medications to help with pain.

More severe cases may result in pericardial tamponade, a buildup of fluids that increases pressure on the heart. This may require emergency drainage of excess fluids. In rare cases, some children may need surgery.

If the pericarditis is caused by an infection, the doctor may prescribe antibiotics or other medications to treat the infection.