Pericarditis is a condition in which the sac-like covering around the heart (pericardium) becomes inflamed. The cause of pericarditis is often unknown or unproven, but is often the result of an infection such as:
- Viral infections that cause a chest cold or pneumonia, such as the echovirus or coxsackie virus (which are common in children), as well as influenza
- Infections with bacteria (much less common) and some fungal infections (even more rare)
Other causes include:
- Heart attack
- Heart surgery or trauma to the chest, esophagus, or heart
- Certain medications and some drugs used to treat cancer or suppress the immune system
- Swelling or inflammation of the heart muscle
Source: NIH.gov