Pericarditis is inflammation of the pericardium, which is the thin sac that surrounds the heart and the roots of the great vessels. There is normally a small amount of fluid between the inner and outer layers of the pericardium. When the pericardium becomes inflamed, the amount of fluid between its two layers increases, compressing the heart and interfering with its ability to function properly. Typically, the cause of pericarditis is unknown, but may include these causes:

• a viral, bacterial or fungal infection
• heart attack
• cancer spreading from a nearby tumor in the lung, breast or the blood
• sometimes it may be a secondary symptom of rheumatoid arthritis, lupus (systemic lupus erythematosus), or kidney failure

How is pericarditis treated?
Pericarditis is usually treated with analgesics or anti-inflammatory drugs to relieve pain. When excess fluid seriously affects the heart's action, it may be drawn off with a needle. In some cases, surgery may be required.

Acute inflammatory pericarditis usually lasts two to six weeks. About 20% of pericarditis patients have a recurrence within months or, sometimes, years later. Each recurrence tends to be less severe until the episodes finally stop.