Question
How does the sac that surrounds the heart become infected?
Answer
The “sac that surrounds the heart” is called the pericardium. The pericardium is a fibroelastic sac that contains 15 to 50 cc of fluid and surrounds and protects the heart. Pericarditis, or an inflammation of the pericardium, is not rare. True infections that require specific treatment are very unusual.
Pericarditis may present with chest pain, along with changes on the electrocardiogram, and a specific sound heard through the stethoscope called a “friction rub.” An ultrasound picture of the heart will show an increase in the usual amount of fluid present in the pericardial sac.
Eighty-three percent of pericarditis cases are viral or idiopathic and are a benign condition that resolves with anti-inflammatory drugs. This type of pericarditis often occurs after a viral illness. Of the remaining cases, five percent are caused by malignancies, four percent are caused by tuberculosis, five percent are caused by autoimmune diseases such as lupus, scleroderma, or rheumatoid arthritis, and only one percent are caused by purulent (infected) pericarditis, which require antibiotics and drainage. Pericarditis can be frequently seen after open heart surgery and can also be associated with severe renal failure.
If someone has chest pain, it is important to differentiate pericarditis from life-threatening problems such as heart attack, pulmonary emboli (blood clots to the lung), or aortic dissection (a tear of the wall of the aorta). The type of pericarditis determines the proper treatment.