Friday, December 19, 2014

Definition

Pericarditis is an inflammation of the pericardium, the membrane forming the outer covering of the heart.

Description

The inflammation may cause a thickening and roughening of the membrane and an accumulation of fluid in the sac surrounding the heart.

Causes

Causes and Risk Factors

Pericarditis in the U.S. is often caused by a viral infection. The disease may also be caused by bacteria (including mycobacterium tuberculosis), fungi, or parasites.

There is also a noninfectious pericarditis that can be caused by disease of the underlying heart muscle, injury, cancer, and other diseases such as rheumatoid arthritis, medications (minoxidil, penicillin), lupus erythematosus, and kidney failure.

Even young, otherwise healthy individuals can develop pericarditis following what initially appears to be a routine viral illness. Viruses such as those that cause flu, mumps and mononucleosis, as well as HIV, hepatitis, and varicella, have all been associated with pericarditis. Typically, one to three weeks after a viral illness, patients begin to experience fever, chest discomfort, cough, shortness of breath, and general malaise.

Early detection and treatment are important to prevent potentially serious complications. For example, untreated bacterial, TB or chronic pericarditis may cause the pericardium to lose its elasticity, causing a constriction of the heart. If the heart is unable to function normally because of pericardial constriction, surgery to remove part of the pericardium may be required.

Another potentially serious complication of pericarditis, especially that caused by a bacterial infection, injury, or tumor, is cardiac tamponade (stoppage of the flow of blood) which is caused by an accumulation of fluid in the pericardial sac, resulting in excessive pressure on the heart. If untreated, blood pressure will drop along with cardiac output. This is an emergency situation that is treated by puncturing the pericardial sac to remove the fluid.

Symptoms

Acute pericarditis may cause pain in the center of the chest which can radiate to the neck or left shoulder. Unlike angina or heart attack, this pain may be "sticking" in nature and worsens with deep breathing, coughing, or twisting of the upper body. Nevertheless, the pain at times may mimic that of a heart attack. When acute pericarditis is triggered by infection, fever, chills, and weakness also tend to occur.

Chronic pericarditis may not cause any symptoms until the long-term inflammation of the pericardium causes it to thicken and contract to the point where it interferes with normal heart filling. This condition is known as constrictive pericarditis. Pain may not be a prominent symptom, but symptoms that mimic heart failure may develop, including shortness of breath and edema (accumulation of fluid in the legs and abdomen), swelling in the abdomen because of fluid (ascites), and swelling of the liver.

Diagnosis

The medical history and physical examination are important. When listening with a stethoscope, the doctor may hear a grating sound as the heart moves, called a pericardial friction rub. In addition, if acute inflammation has caused accumulation of fluid in the pericardial sac, the doctor may note changes in sounds produced by the heart - increased cardiac dullness, diminished or absent apical impulse, and distant heart sounds.

Blood tests, such as white blood cell count and measurement of cardiac enzymes, may help to confirm inflammation and identify its cause. Open surgical drainage or cardiocentesis may be performed to obtain a culture of pericardial fluid. An electrocardiogram (EKG) may show changes in heart rate and rhythm brought on by acute inflammation.

Treatment

Analgesics (pain medications), ranging from aspirin to morphine, as well as anti-inflammatory drugs may be given to ease the pain or reduce the inflammatory reaction of acute pericarditis. No further treatment may be necessary for pericarditis caused by a viral infection, which tends to clear by itself within a few weeks. If an underlying treatable cause for the pericarditis can be identified, further treatment will be directed towards its alleviation.

Antibiotics may be given for a bacterial or TB infection, while steroids and non-steroidal anti-inflammatory agents such as indomethacin may be given in other cases. Steroid drugs may also be prescribed to reduce the inflammation in pericarditis resulting from a heart attack. Diuretics and a salt-restricted diet are also recommended for constrictive pericarditis.

Although viral pericarditis usually resolves on its own, patients are sometimes admitted to the hospital for observation, particularly if there is any concern that something more serious could be causing the symptoms or if there is evidence of a large collection of fluid within the pericardial space. Viruses that cause pericarditis can sometimes attack the heart muscle and therefore, in rare cases, patients also develop heart-rhythm abnormalities or heart failure.

For most people who develop viral or idiopathic pericarditis, the disease is a temporary annoyance that is forgotten after it resolves. About one-fourth of patients, however, develop subsequent episodes of pericarditis, recurring at intervals of weeks or months. In these patients, anti-inflammatory agents can usually control the symptoms.

A small number of patients develop so much fluid that their hearts cannot beat effectively. In these instances, the fluid must be removed by an experienced cardiologist or cardiothoracic surgeon.

Rarely, patients can develop chronic scarring of the pericardium, which can be severe enough to keep the heart from expanding normally in between heart beats. Since the heart cannot fill adequately, the heart's ability to supply blood to the rest of the body slowly declines as the scarring gets worse. This problem is called constrictive pericarditis and often requires surgery to "strip" the pericardium away from the heart.

Questions

What tests need to be done to diagnose and to determine the cause and extent of involvement?

What is the cause of the pericarditis?

What type of treatment will you be recommending?

What medications will you be prescribing? What are the side effects?

How successful is this treatment? And how soon will symptoms decrease or disappear?

Has any permanent damage been done to the heart muscle?

Will I be susceptible to pericarditis again?