Pericarditis

Definition
Pericarditis is an inflammation of the pericardium, a membrane that surrounds the heart.

Anatomy
The pericardium, also called the pericardial sac, consists of a membrane that surrounds the heart and cushions it in a thin layer of fluid. The pericardium protects the heart from motion and sudden increases in size during times of increased volume, such as during exercise. When the heart beats, the pericardium decreases friction from the other organs in the chest.

Causes/associated factors
Often, the cause of pericarditis is unknown. It typically develops in young to middle-aged people, and men are affected slightly more often than women. It develops most often after a viral respiratory infection, heart attack or coronary bypass graft procedure. Other possible causes include radiation therapy to the chest, kidney failure, fungal or parasitic infections, hypothyroidism, rheumatoid arthritis, lupus and other connective tissue diseases, tuberculosis, cancer, certain medications, heart attack, and injury or trauma to the chest. Pericarditis may be acute (sudden) or chronic (long-term).

Signs/symptoms
Sharp chest pain is the primary symptom of pericarditis. It may appear gradually or suddenly. The pain often felt under the breastbone over the center or left side of the chest. The pain may radiate to the left shoulder blade or the top of the left shoulder or arm, as well as the back or neck. Exertion or exercise does not worsen the pain. You may also notice dull chest pain. In either case, the chest pain usually becomes worse when lying down (especially on the left side), coughing or taking a deep breath. To ease the pain, sit up and lean forward, or try to lie still and take shallow breaths.
Other symptoms can include:

painful or difficult swallowing
rapid breathing
rapid heart rate
cough
fever and chills
weakness
anxiety
difficulty breathing
muscle or joint pain
peripheral edema (swelling)
fatigue

Diagnosis
The doctor will ask questions about your medical history and current symptoms and do a physical exam. The key finding is a scratchy sound ("rub") the doctor hears with the stethoscope over the heart. The doctor may also recommend one or more of the following tests:
echocardiogram (using sound waves to look at the heart without penetrating the skin)
electrocardiogram (a recording of the electrical activity of the heart)
chest X-ray
computed tomography (CT scan -- a computer-generated, cross-sectional image of the chest) or magnetic resonance imaging (MRI, an imaging technique based on computer analysis of the body's response to a magnetic field)
Blood tests may also be done to check for underlying diseases or inflammation, and skin tests may be used to check for tuberculosis or fungal infections. Fluid may be removed from the pericardial sac for examination in a lab.


Treatment
With proper treatment, symptoms usually clear up within two to six weeks. For some people, however, symptoms last longer or recur. Depending on the underlying cause, aspirin or nonsteroidal anti-inflammatory pain relievers are commonly recommended. In some cases, steroid medications are prescribed to reduce inflammation. If tuberculosis is responsible for the condition, your doctor may prescribe antibiotics to treat the tuberculosis. The doctor may also recommend that you rest.
Chronic or recurring pericarditis is uncommon. These cases are best treated with steroids or a medication called colchicine. Rarely, drugs to suppress your immune system may be used. In severe cases, a surgical procedure known as pericardiectomy may be recommended. The procedure improves the heart's pumping function by "stripping" the pericardium from the surface of the heart. Many people who have acute pericarditis are hospitalized for observation and treatment.


Complications
If fluid accumulates between the heart and the pericardium, you may develop a condition known as pericardial effusion. If too much fluid accumulates, the resulting pressure on the heart can interfere with the heart's ability to pump. This fluid may need to be removed with a needle and catheter (a flexible tube) through a procedure called pericardiocentesis.
Another potential complication is pericardial constriction, a condition in which the pericardium becomes stiff, squeezing the heart like a girdle, which can interfere with your heart's ability to pump. This problem may be treated by surgically removing the pericardium.

If fluid rapidly builds up in the pericardial sac without giving the pericardium time to gradually expand and the heart chambers to fill with blood, an emergency condition called cardiac tamponade may develop. This condition can prevent the heart from pumping, causing low blood pressure or shock. Symptoms of cardiac tamponade include vague chest tightness, profound fatigue, shortness of breath, a fast heart rate and palpitations. The fluid needs to be drained either by a needle, catheter or surgery. Because cardia tamponade is sometimes fatal, the fluid must be removed in an emergency surgical procedure.


Pregnancy-specific information
Pregnancy is not considered a risk factor for the development of pericarditis. If you develop pericarditis while you're pregnant, treatment will depend on your medical condition. Discuss any individual concerns with your doctor.

Senior-specific information
Older adults have a lower rate of pericarditis than young and middle-aged adults.

Prevention
Pericarditis is not preventable. Prompt treatment can help prevent complications, however.