The medical term for fluid in the space surrounding the heart is “pericardial effusion.” Our major organs, including the heart, have linings that usually have no significant fluid within them. In a number of conditions, fluid may accumulate around the heart.
One of the most common ways this fluid is detected is by echocardiography. This is a common and painless test in which sound waves are bounced off the heart to get detailed images of the heart’s valves, muscle function and pericardium (heart lining). It is important to recognize that there may be a small amount of pericardial fluid in people who are healthy, with perfectly normal hearts.
When caused by illness, pericardial effusion may cause no symptoms. Or it may cause pain or reduced heart function. A number of conditions can lead to pericardial effusion. These include:
- Infection. Viral, bacterial, and tuberculous infections are the most common.
- Rheumatic (or Connective Tissue) Diseases. Lupus is the most common rheumatic disease to cause inflammation of the pericardial lining (called “pericarditis”). Some medications can contribute to “drug-induced lupus” and cause the same problem.
- Heart failure or a heart attack (myocardial infarction).
- Trauma. Blood may enter the pericardial space when the heart or chest is injured.
- Tumor. Cancer involving nearby lung or the heart lining itself is a rare cause.
- Kidney failure. For reasons that are not well-understood, people with severe renal failure (usually those in need of dialysis) may develop pericarditis and effusion.
- Low protein state. When the body’s blood protein levels are very low — as may happen with severe malnutrition or cirrhosis — fluid may accumulate throughout the body, including the heart.
There are other rare causes. These include an underactive thyroid, radiation therapy and aortic aneurysm (an abnormal swelling of the major artery leaving the heart). But sometimes, no cause is ever found (termed “idiopathic”).
The treatment of pericardial effusion depends on its cause, how much fluid is present and how quickly it develops. When possible, treating the underlying disorder (such as heart failure) often reduces or cures the pericardial effusion. Doctors often prescribe pain medicine and anti-inflammatory drugs such as aspirin or ibuprofen for symptoms. Exclusion of an infectious cause (by removing a small sample of fluid through a needle or by a pericardial biopsy) is often necessary before starting treatment. Emergency removal of fluid may be necessary if the fluid is preventing the heart muscle from functioning normally. This is a rare situation called “cardiac tamponade.” It’s more likely if the amount of pericardial fluid is large or developed quickly.
Antibiotic agents are effective for pericardial effusions due to bacteria or tuberculosis. However, the fluid must often be drained to speed up recovery and improve heart function. Viral infections typically improve on their own within a week or two. For rheumatic diseases, corticosteroids and, in some cases, immune-suppressing drugs are usually effective. Traumatic causes and any type that does not respond to more conservative treatment may require surgery to allow ongoing drainage. Treatment of the underlying cancer or low protein state may improve pericardial effusions related to these conditions. Dialysis is generally effective for those associated with kidney failure.
The specifics of each case are critical to figuring out whether a pericardial effusion is an unimportant finding or an urgent and life-threatening condition. Treatment decisions are directed by the underlying cause and the person’s overall condition.