Pericardial effusion (per-e-KAHR-dee-ul uh-FU-zhun) occurs when too much fluid builds up around the heart.
The heart is surrounded by a double-layered, sac-like structure called the pericardium. The space between the layers normally contains a very small amount of fluid.
But if the pericardium is diseased or injured, the resulting inflammation can lead to pericardial effusion. Fluid can also build up around the heart without inflammation. Sometimes, pericardial effusion can be caused by the accumulation of blood after a surgical procedure or injury.
When the amount of fluid exceeds the pericardium’s “full” level, pericardial effusion puts pressure on the heart, causing poor heart function. If left untreated, pericardial effusion can cause heart failure or even death.
Inflammation of the pericardium (pericarditis) is a response to disease, injury or an inflammatory disorder that affects the pericardium. Pericardial effusion is often a sign of this inflammatory response.
Pericardial effusion may also occur when the flow of pericardial fluids is blocked or when blood accumulates within the pericardium. It’s not clear how some diseases contribute to pericardial effusion, and sometimes the cause can’t be determined.
Specific causes of pericardial effusion may include:
- Viral, bacterial, fungal or parasitic infections
- Inflammation of the pericardium due to unknown cause (idiopathic pericarditis)
- Inflammation of the pericardium following heart surgery or a heart attack (Dressler’s syndrome)
- Autoimmune disorders, such as rheumatoid arthritis or lupus
- Waste products in the blood due to kidney failure (uremia)
- Underactive thyroid (hypothyroidism)
- Spread of cancer (metastasis), particularly lung cancer, breast cancer, melanoma, leukemia, non-Hodgkin’s lymphoma or Hodgkin’s disease
- Cancer of the pericardium or heart
- Radiation therapy for cancer if the heart was within the field of radiation
- Chemotherapy treatment for cancer, such as doxorubicin (Doxil) and cyclophosphamide (Cytoxan)
- Trauma or puncture wound near the heart
- Certain prescription drugs, including hydralazine, a medication for high blood pressure; isoniazid, a tuberculosis drug; and phenytoin (Dilantin, Phenytek, others), a medication for epileptic seizures
You can have significant pericardial effusion and experience no signs or symptoms, particularly if the fluid has increased slowly.
If pericardial effusion symptoms do occur, they may include:
- Shortness of breath or difficulty breathing (dyspnea)
- Discomfort when breathing while lying down (orthopnea)
- Chest pain, usually behind the breastbone or on the left side of the chest that often feels worse when you breathe and feels better when you are sitting up, rather than lying down
- Low-grade fever
- Rapid heart rate
When to see a doctor
Call 911 or your local emergency number if you feel chest pain that lasts more than a few minutes, if your breathing is difficult or painful, or if you have an unexplained fainting spell. If you experience shortness of breath, fatigue or other symptoms of pericardial effusion, see your doctor.