Pericarditis is swelling (inflammation) of the pericardium - the sac which surrounds the heart. Pericarditis causes chest pains. Most cases are due to a viral infection which usually goes away within a few weeks. The only treatment usually needed for a 'viral pericarditis' is anti-inflammatory medication. There are some less common causes of pericarditis which may need other treatments. Complications are uncommon, but can be serious.
What are the pericardium and pericarditis?
The pericardium is a thin sac-like tissue that covers the outer surface of the heart. It helps to anchor the heart in place, and prevents the heart from moving in the chest when you move. The pericardium has an inner and outer layer. There is a thin layer of 'lubricating' fluid between the two layers.
Pericarditis means swelling (inflammation) of the pericardium.
What are the causes of pericarditis?
Infection with a virus is the most common cause. Several different viruses can cause pericarditis, including Coxsackieviruses, echoviruses, influenza viruses, adenoviruses, the mumps virus, human immunodeficiency virus (HIV) and viruses that cause hepatitis.
Other causes are uncommon and include:
- Infection with a germ (bacterium). This often causes pus to form between the inner and outer layers of the pericardium. The infection has usually spread from nearby tissues (such as an infection of the heart itself) or from a wound infection following heart surgery. Rarely, syphilis or fungi can infect the pericardium.
- Tuberculosis (TB) infection. This is usually as part of a more widespread TB infection in the lungs and other parts of the body.
- Uraemic pericarditis. This is swelling (inflammation) caused by waste products building up in the bloodstream in people with untreated kidney failure.
- Heart attack (myocardial infarction). Inflammation of the pericardium may occur if there is damage to nearby heart tissue, caused by a heart attack.
- Following heart surgery. Inflammation can occur a few days to a few weeks after open heart surgery.
- Following injury. For example, following a stab wound, or a severe blow to the chest.
- Inflammatory diseases which can affect various parts of the body may include inflammation of the pericardium. For example, rheumatoid arthritis, scleroderma, polyarteritis nodosa, and systemic lupus erythematosus (SLE).
- Radiotherapy to treat cancers in the chest.
- Cancer which has spread to the pericardium from another part of the body (this is very rare).
In many cases, no cause can be found. This is called idiopathic pericarditis. Many of these cases are probably caused by a viral infection which is not able to be identified.
What are the symptoms of pericarditis?
Symptoms of viral and idiopathic pericarditis
The typical symptoms are chest pain and high temperature (fever). The pain is usually in the middle of the chest or slightly left of centre. It may feel sharp and stabbing. Sometimes it is a persistent steady pain. The pain may spread to the neck and/or shoulders. Typically, the pain gets worse if you take a deep breath, swallow, cough, or lie down. The pain may ease if you sit up or lean forward.
You may also feel breathless, especially if tamponade develops (see below).
Symptoms of other causes of pericarditis
These may be similar to viral pericarditis. Depending on the underlying cause of the pericarditis, there may also be various other symptoms.
What are the possible complications of pericarditis?
Complications are uncommon. They include the following:
Build-up of fluid
In many cases of pericarditis a small amount of fluid builds up between the two layers of the pericardium. This is called a pericardial effusion.
A small amount of fluid is no problem and usually goes when the swelling (inflammation) settles. However, sometimes a lot of fluid builds up and can press on the heart. This can prevent the heart chambers from filling normally, and prevents the heart from pumping blood properly. This is called cardiac tamponade and is a life-threatening problem unless the fluid is quickly drained. Severe breathlessness can develop quickly within minutes or hours. If this happens, you should see a doctor urgently.
This is an uncommon condition that may develop if the pericardium has been inflamed for a long time. The pericardium thickens and contracts around the heart. This is serious, as it can interfere with the function of the heart.
With both of the above complications, symptoms include shortness of breath which gets worse and worse. Other symptoms of constrictive pericarditis may include swollen legs and ankles and tiredness.
How is pericarditis diagnosed?
When a doctor listens to your chest with a stethoscope, he or she may hear a typical sound which occurs with pericarditis. It is called a pericardial friction rub. It sounds like a grating noise. This does not occur in all cases.
Other conditions can cause similar symptoms to pericarditis. Therefore, tests may be needed to clarify the diagnosis, and to rule out other causes of chest pain:
- A chest X-ray may show a change in the shape of the heart (a flask-shaped heart) or fluid in the lung cavity.
- An electrocardiogram (ECG). This is a tracing of the electrical activity of the heart. It sometimes shows typical patterns if you have pericarditis.
- An echocardiogram, which is an ultrasound scan of the heart. This shows the structure of the heart and surrounding tissues. It can detect if any fluid has built up between the layers of pericardium, which is typical of pericarditis.
- Other tests such as a magnetic resonance imaging (MRI) scan or computed tomography (CT) scan may be needed to look for changes in the pericardium. These tests tend to be done if a cause other than a viral infection is suspected.
- If a large pericardial effusion develops, a sample of the fluid may be taken with a needle and syringe and analysed for infections such as TB.
What is the treatment for pericarditis?
Treatment for viral or idiopathic pericarditis
Anti-inflammatory medicines such as ibuprofen are usually given to ease the pain and reduce swelling (inflammation). If the condition carries on for more than 14 days you may also be given a medicine called colchicine, which helps to improve the outcome and reduce the chances of the inflammation coming back. If the pain is severe and you are not getting better with ibuprofen and colchicine, steroid medicines may be used to reduce the inflammation. The pain and inflammation usually settle within a few weeks.
Treatment for other causes and for complications
The treatment depends on the cause. For example, antituberculosis medication for TB, antibiotic medicines for germ (bacterial) infections, intensive dialysis for uraemic pericarditis, etc. If a lot of fluid builds up and causes cardiac tamponade, the fluid needs to be drained with a needle and syringe. If constrictive pericarditis develops and interferes with the heart's function, the thickened pericardium may need to be removed by an operation. This is called a pericardiectomy.
What is the outlook (prognosis) if you have pericarditis?
Most people with viral or idiopathic pericarditis recover fully within a few weeks, without any complications. However, in some cases the symptoms return 'on and off' for several months.
Pericarditis caused by heart attack or injury usually settles over one to two weeks. The outlook for other forms of pericarditis (uraemic, bacterial, TB, etc - see above) can vary depending on the severity of the underlying cause.
Further help & information
Dr Tim Kenny
Dr Louise Newson
Dr Helen Huins