Pericarditis is inflammation (swelling) of the pericardium, which is the fluid-filled sac that surrounds your heart.
The main symptom of pericarditis is a sudden, sharp stabbing pain behind your breastbone. This usually worsens when lying down. See Pericarditis – Symptoms for more information.
Pericarditis is not usually a serious condition and can often be treated on an outpatient basis, so you do not have to be admitted to hospital.
The pericardium
The pericardium is a double-layered sac that surrounds the heart. The two layers are separated by around 35ml (about an eggcup-full) of fluid.
The pericardium has three important functions, acting as:
- a shock absorber, protecting the heart from injury and changes in blood pressure
- a lubricant; the fluid inside the pericardium protects the heart from friction, enabling it to pump easily and efficiently
- an anchor, keeping the muscles of the heart firmly connected to the wall of the chest
Because of its important role in protecting and regulating the heart, inflammation of the pericardium can quickly result in severe chest pain, even though the underlying damage to the heart is often minimal.
Types of pericarditis
There are three main types of pericarditis:
- acute pericarditis – where the symptoms do not last longer than three months (with treatment, symptoms normally resolve within a week)
- recurring pericarditis – where someone has repeated episodes of acute pericarditis
- chronic pericarditis – where the symptoms last longer than three months
Each type is discussed in more detail below.
Acute pericarditis
It is thought that most cases of acute pericarditis are the result of a viral infection. However, current tests are poor at confirming whether this is true, and in up to 90% of cases no clear cause can be found. When the cause is unknown, it is termed idiopathic pericarditis.
Recurring pericarditis
It is estimated that one-in-four people with a previous history of acute pericarditis will develop recurring pericarditis.
The exact cause of recurring pericarditis is unclear. It may be caused by the immune system (the body’s natural defence against infection) mistakenly reacting to a previous infection.
Chronic pericarditis
The symptoms of chronic pericarditis are usually milder than those of acute pericarditis.
Chronic pericarditis can be the result of an underlying health condition such as tuberculosis, but in most cases no obvious cause can be found.
As with recurring pericarditis, it may be that problems with the immune system are responsible for many cases of chronic pericarditis. For more information on chronic pericarditis, see Pericarditis – Complications.
How common is pericarditis?
Pericarditis is a relatively common heart condition. Around 5% of all admissions to accident and emergency (A&E) departments for severe chest pain are due to pericarditis.
Pericarditis tends to be more common in men than women. It can affect people of all ages but mostly occurs in adults.
Outlook
Acute pericarditis can usually be treated with medication such as non-steroidal anti-inflammatory drugs (NSAIDs).
A medication called colchicine is often effective for recurring pericarditis, as it can prevent symptoms returning.
The outlook for chronic pericarditis will depend on the underlying cause. Some cases respond well to medication, while others may require surgery to treat. See Pericarditis – Treatment for more information.
