Pericarditis is usually a complication of viral infections, most commonly echovirus or cocksackie viruses. Less frequently, it can be caused by influenza or HIV infection. Infections with bacteria can lead to bacterial pericarditis (also called purulent pericarditis). Some fungal infections can also produce pericarditis.

In addition, pericarditis can be associated with systemic diseases such as autoimmune disorders, rheumatic fever, tuberculosis, cancer, leukemia, kidney failure, HIV infections, AIDS and hypothyroidism.

Heart disorders that can cause pericarditis include heart attack (see post-MI pericarditis) and myocarditis. Radiation therapy to the chest and medications that suppress the immune system can also sometimes induce this condition.

Pericarditis can also result from injury (including surgery) or trauma to the chest, esophagus, or heart.

Quite often, the cause of pericarditis remains unknown, in which case it is called idiopathic pericarditis.

Pericarditis most often affects men aged 20-50, usually following respiratory infections. It can also occur in children, where it is most commonly caused by adenovirus or coxsackie virus.

• Chest pain, caused by the inflamed pericardium rubbing against the heart.
  • Usually relieved by sitting up and leaning forward
  • Pleuritis type: a sharp, stabbing pain
  • May radiate to the neck, shoulder, back or abdomen
  • Often increases with deep breathing and lying flat; may increase with coughing and swallowing
• Breathing difficulty when lying down (the patient prefers standing or sitting upright)
• Splinting of ribs (bending over or holding the chest) with breathing
• Dry cough
• Ankle, feet and leg swelling (occasionally)
• Anxiety
• Fatigue
• Fever

When listening to the heart with a stethoscope, the health care provider can hear a typical sound called a pericardial rub. The heart sounds may be muffled or distant. There may be other signs of fluid in the pericardium (pericardial effusion).

If the disorder is severe, there may be crackles in the lungs, decreased breath sounds, or other signs of fluid in the space around the lungs (pleural effusion).

If fluid has accumulated in the pericardial sac, it may show on:

• Chest X-ray
• Echocardiogram
• Chest MRI scan
• Heart MRI or heart CT scan
• Radionuclide scanning

These tests show enlargement of the heart from fluid collection in the pericardium, and signs of inflammation. They may also show scarring and contracture of the pericardium (constrictive pericarditis). Other findings vary depending on the cause of pericarditis.

An ECG is abnormal in 90% of patients with acute pericarditis. The ECG changes generally evolve in stages during the disease process, and they may mimic the ECG changes of a heart attack. To rule out heart attack, serial cardiac marker levels (CK-MB and troponin I) may be ordered. Other laboratory tests may include:

• blood culture
• CBC, may show increased WBC count
• C-reactive protein
• erythrocyte sedimentation rate (ESR)
• pericardiocentesis with chemical analysis and pericardial fluid culture

The cause of pericarditis must be identified, if possible.

In most types of pericarditis, it is necessary to treat the pain with analgesics (pain killers). The inflammation of the pericardium is treated with anti-inflammatory drugs(NSAIDS) such as aspirin and ibuprofen; in some cases, corticosteroids may be prescribed.

Diuretics may be used to remove excess fluid accumulated in the pericardial sac. If the buildup of pericardial fluid makes the heart function poorly or produces cardiac tamponade, it is necessary to drain the fluid through pericardiocentesis (removal of excess fluid from the pericardial sac).

Pericardiocentesis may be either percutaneous (using a needle to reach the pericardium, guided with echocardiography, in the procedure room), or surgical (done in the operating room as a minor surgery).

Bacterial pericarditis should be treated with antibiotics. Fungal pericarditis should be treated with antifungal agents.

If the pericarditis is chronic, recurrent, or results in constrictive pericarditis, it may be advisable to perform pericardiectomy (cutting or removal of part of the pericardium).

• Arrhythmias, such as atrial fibrillation. When pericarditis accompanies myocarditis, other arrhythmias may be present, such as supraventricular tachycardia (SVT) or complete heart block.
• Cardiac tamponade
• Constrictive pericarditis, where inflammation of the pericardial sac results in fibrosis and thickening of the pericardium with adhesions (i.e., sticky scars) between the pericardium and the heart. The pericardium creates a rigid "case" around the heart and can severly limit the ability of the heart to fill with blood during diastole (i.e., the relaxation phase before the next heartbeat). Patients with constrictive pericarditis may develop heart failure which responds poorly to treatment. Constrictive pericarditis needs to be differentiated from a chronic heart condition called restrictive cardiomyopathy, which produces symptoms and signs similar to constrictive pericarditis.