Key Terms: Pericardium, Sclerosing agents, Tamponade.
Definition
A pericardial effusion is a fluid collection that develops between the pericardium, the lining of the heart, and the heart itself. Pericardial effusions can be found in up to 20% of cancer patients at autopsy, but of those, only about 30% would have had symptoms from their effusions.
Description
Most of the organs of the body are covered by thin membranes. The membrane that surrounds the heart is called the pericardium. Normally, only a few milliliters of fluid sit between the pericardium and the muscle of the heart. Any larger, abnormal collection of fluid in that space is called a pericardial effusion.
A pericardial effusion can interfere with the normal contraction and expansion of the heart muscle, which decreases the heart's ability to pump blood effectively. A large or rapidly developing effusion can cause a condition called cardiac tamponade. Tamponade is a medical emergency and can be fatal if not diagnosed and treated promptly. Symptoms of tamponade include shortness of breath, rapid pulse, cough, and chest discomfort. As tamponade progresses, low blood pressure and shock develop and cardiac arrest can follow.
A smaller or more slowly developing pericardial effusion also causes chest discomfort. Other symptoms, such as shortness or breath, difficulty swallowing, hoarseness or hiccups result from pressure from the enlarged, fluid-filled pericardium pressing against nearby organs. Although chronic or smaller effusions are not emergencies, they do cause discomfort and can become more serious.
The diagnosis of pericardial effusion is made on the basis of patient history, physical examination and appropriate laboratory studies. Heart sounds can be muffled, the veins in the neck engorged and the pulse rapid. A chest x ray shows enlargement of the silhouette of the heart. An echocardiogram or cardiac ultrasound will show the fluid surrounding the heart, as will CT and MRI scans.
Causes
A pericardial effusion in a cancer patient is caused either by the disease itself or by the treatment for the disease.
Many cancers can metastasize or spread to the pericardium or the heart itself. They include:
- Lung
- Breast
- Thyroid
- Esophagus
- Kidney
- Pancreas
- Endometrium
- Larynx
- Cervix
- Stomach
- Mouth
- Liver
- Ovary
- Colon
- Prostate
- Leukemia
- Melanoma
- Lymphoma
- Sarcoma
- Myeloma
The presence of the cancerous cells on the pericardium is an irritant and causes a reactive fluid buildup, much as a blister forms under the skin due to irritation. Some cancers cause less fluid buildup, instead thickening the pericardium and making it less elastic. This can also cause symptoms of tamponade.
Another cause of pericardial effusion in a cancer patient is previous radiation therapy to the chest, especially in the case of lung cancer or lymphoma. While such effusions are less likely to produce tamponade, it is possible.
Many of the drugs that are used to treat cancer can cause pericardial disease and can thus potentially cause pericardial effusions. Some of the chemotherapeutic drugs that can affect the pericardium are cytarabine, fluorouracil, cyclophosphamide, doxorubicin and daunorubicin. Granulocyte-macrophage colony-stimulating factor (sargramostim), often given to help increase the population of white blood cells during intensive chemotherapy, is also a pericardial irritant.
Other causes of pericardial effusions are heart failure, liver disease, and kidney disease. Any of these can also affect cancer patients.
Treatments
Treatment of pericardial effusion depends on the presence or absence of cardiac tamponade. Tamponade is a medical emergency and symptoms such as cyanosis, a blue tinge to the lips and skin, shock, or a change in mental status require urgent drainage of the fluid. This drainage is accomplished with a procedure called pericardiocentesis, in which a needle is inserted into the pericardial space and the fluid withdrawn into a large syringe. Chronic effusions can be drained electively, and some need not be drained at all. If a patient's prognosis is poor and the pericardial effusion is not compromising the function of the heart, the risks of a drainage procedure may outweigh its benefits and the effusion may be left alone. Effusions caused by lymphoma often resolve after aggressive chemotherapy and need no further treatment.
Elective drainage of a pericardial effusion is done by one of several surgical procedures. The surgeon might open the chest, make a small incision under the bottom of the breastbone, or use a video-assisted technique called thoracoscopy. In addition to permitting drainage of the pericardial fluid, these procedures permit the surgeon to take a pericardial biopsy, which can confirm the diagnosis of metastatic cancer.
Sometimes a catheter is placed in the pericardium and connected to an external drainage system to collect any fluid that might reaccumulate.
Occasionally, sclerosing agents—drugs that cause scarring—are infused into the pericardium through a catheter. These agents, such as tetracycline, minocycline or bleomycin, irritate the pericardium, causing it to thicken and adhere to the heart muscle. This scarring prevents the further accumulation of fluid. Some malignant pericardial effusions resolve after the instillation of chemotherapeutic drugs such as thiotepa or platinum directly into the pericardial cavity. Others resolve after radiation therapy directed at the pericardium.
Alternative and Complementary Therapies
No complementary or alternative treatments are aimed specifically at treating pericardial effusions, but practitioners of acupressure and acupuncture designate a pressure point for the pericardium at two and a half finger breadths above the wrist crease on the inner aspect of the arm. Acupressure and acupuncture do offer some relief of symptoms to those suffering from shortness of breath and might offer benefit to those with pericardial effusions.
Resources
Books
Moore, Katen, and Libby Schmais. Living Well with Cancer: A Nurse Tells You Everything You Need to Know About Managing the Side Effects of Your Treatment. New York: Putnam Publishing Group, 2001.
Periodicals
Bastian, A., et. al. " Pericardiocentesis: Differential Aspects of a Common Procedure." Intensive Care Medicine 26, no. 5 (May 2000): 572-6.
Brigden, M. L. "Hematologic and Oncologic Emergencies. Doing the Most Good in the Least Time." Postgraduate Medicine 109, no. 3 (March 2001): 143-6, 151-4, 157-8.
Gibbs, C. R., R. D. Watson, S.P. Singh, and G.Y. Lip. "Management of Pericardial Effusion by Drainage: A Survey of 10 Years' Experience in a City Centre General Hospital Serving a Multiracial Population." Postgraduate Medicine Journal 76, no. 902 (December 2000): 809-13.
Other
Heart Center Online Home Page. [cited June 6, 2001].
—Marianne Vahey, M.D.
