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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.


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.

Cardiac tamponade

In a few cases, pericarditis can trigger a serious complication known as cardiac tamponade. This is an excess build-up of fluid inside the pericardium. The extra fluid places too much pressure on the heart, so it is unable to beat properly.

Cardiac tamponade can be potentially life-threatening and requires immediate treatment. See Pericarditis – Complications for more information.

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Acute pericarditis

The most common symptom of acute pericarditis is chest pain.

Chest pain

Most people who have had acute pericarditis describe experiencing a sudden sharp pain usually behind their breastbone, on the left side of their body. Some people describe the pain as more like a dull ache or feeling of pressure.

The pain may also radiate up from your chest into your left shoulder and neck.

It is usually worse when coughing, eating and lying down. Sitting up or leaning forward will usually help relieve the pain.

The pain can range from mild to severe.

Additional symptoms

Depending on the underlying cause of your acute pericarditis, you may also experience:

  • a mild fever, usually 38-39C (100.4-102.2F)
  • shortness of breath while lying down
  • fatigue
  • nausea
  • dry cough
  • swelling of the legs or abdomen

Recurring pericarditis

Recurring pericarditis is when you experience frequent episodes of acute pericarditis.

There are two main types of recurring pericarditis:

  • Incessant pericarditis is where the symptoms of acute pericarditis develop once medication such as non-steroidal anti-inflammatory drugs (NSAIDs) are withdrawn. Symptoms usually begin within six weeks of the treatment being withdrawn.
  • Intermittent pericarditis is where you will go for long periods without any symptoms (often many months or sometimes years) before symptoms return without warning.

When to seek medical advice

Always seek immediate medical advice if you experience sudden chest pains. While most cases of pericarditis are not serious, it is important that other more serious conditions are ruled out, such as a heart attack or a blood clot.

Visit your local accident and emergency (A&E) department or telephone NHS Direct Wales on 0845 46 47 as soon as possible.

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Acute pericarditis

In around 90% of cases of acute pericarditis, no obvious cause can be found to explain why the pericardium has become inflamed. Many cases are thought to be the result of viral infections, which current diagnostic technology is generally unable to detect.

Viral infections

Viral infections associated with acute pericarditis include:

Other causes

Other less common causes of acute pericarditis include:

  • bacterial infection, particularly tuberculosis
  • autoimmune conditions such as rheumatoid arthritis or lupus, where the immune system attacks healthy tissues
  • radiotherapy – the radiation used in radiotherapy can damage the tissue of the pericardium, and breast or lung cancer patients may be at particular risk
  • kidney failure (when the kidneys stop working) – exactly why kidney failure causes acute pericarditis is unclear
  • underactive thyroid gland (hypothyroidism) – exactly why hypothyroidism causes acute pericarditis is unclear
  • cancer – cancer that spreads from other parts of the body to the pericardium can damage tissue
  • heart attacks – pericarditis can sometimes develop after a heart attack, as damaged heart muscles can irritate the pericardium
  • injury or irritation to the tissue of the pericardium that occurs during heart surgery
  • severe injury to the chest, for example following a car accident
  • some medications – for example, penicillin or some chemotherapy medicines have been known to trigger acute pericarditis as a side effect in some people

Recurring pericarditis

Despite being a relatively common condition, recurring pericarditis remains a poorly understood condition with little known about the cause.

One theory is that your immune system may be responsible. The theory argues that something goes wrong with your immune system many months or years after the initial infection that caused your first episode of acute pericarditis. It starts to produce infection-fighting antibodies that are meant to be used to fight the virus, but instead are sent to the heart, leading to inflammation of the pericardium. Exactly why the immune system would behave in this way is unclear.

Another theory is that fragments of the virus may lay dormant (inactive) in the tissue of the pericardium and then suddenly reactivate, triggering the process of inflammation.

What is known, is that people treated with corticosteroids during their first episode of acute pericarditis are six times more likely to go on to develop recurring pericarditis than people who do not receive this treatment. Because of this, corticosteroids are used as a last resort, if you fail to respond to other medications. 

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The first stage in the diagnosis of pericarditis is to ask about your symptoms and recent medical history, such as whether you have recently had a chest infection or been in an accident.

The next stage is to listen to your heart with a stethoscope. Pericarditis changes the sound of your heartbeat to a distinctive rasping sound, which is clearly detected by the stethoscope.

You may have blood tests to check for infections, and to check how organs such as your liver and kidneys are functioning.

A diagnosis is usually confirmed by electrocardiogram (ECG). During an ECG, electrodes are placed on your skin to measure the electrical activity of your heart.

People with pericarditis experience a distinctive change in the usual electrical activity of the heart, which can be detected with an ECG.

Further testing

Further testing is only usually required if the test described above proves negative or you have additional symptoms not normally associated with pericarditis, such as swelling of the arms and legs or extreme tiredness.

These tests may include:

  • a magnetic resonance imaging (MRI) scan – an MRI scan uses strong magnetic fields and radio waves to produce a detailed image of the inside of your brain
  • a computer tomography (CT) scan – the scanner takes a series of X-rays and a computer is used to assemble them into a detailed image of the brain
  • an echocardiogram – this test uses sound waves to build up a detailed picture of your heart and pericardium
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Acute pericarditis

Your treatment plan

The medical staff involved in your care will first assess whether it is safe to treat you at home, or whether the risk of complications is high enough for you to be admitted to hospital as a precaution.

Factors that usually lead to an admission to hospital include:

  • having a high temperature (fever) of or above 38C (100.4F)
  • having a high number of white blood cells – this could be the result of a serious infection
  • your symptoms developing after a sudden injury to your chest
  • a history of taking blood thinning medication
  • blood tests showing that you have high levels of a type of protein called troponin in your blood (this can be the result of damage to the heart muscle)

Hospital admission may also be recommended if you fail to respond to the treatment discussed below.

Non-steroidal anti-inflammatory drugs (NSAIDs)

Most cases of pericarditis can be successfully treated with non-steroidal anti-inflammatory drugs (NSAIDs). NSAIDs work by reducing the inflammation of the pericardium. They also relieve the chest pain.

Ibuprofen is the preferred choice of NSAID. The exception is if you have recently had a heart attack, as ibuprofen can interfere with the healing of your heart. In such circumstances, high-dose aspirin will usually be recommended.

As NSAIDs can occasionally cause stomach ulcers, you will probably be prescribed an additional medication called a proton pump inhibitor that provides protection against stomach ulcer.


Colchicine is an additional medicine that can be used if:

  • Your symptoms fail to respond to NSAIDs.
  • You are unable to take NSAIDS because of a pre-existing medical condition.

Colchicine is useful because it kills some of the cells of the immune system that cause inflammation, so can reduce inflammation of the pericardium.

Side effects of colchicine include:

  • abdominal pain
  • vomiting
  • diarrhoea

These side effects usually improve once your body gets used to the medication.


Corticosteroids are usually only given when the symptoms of pericarditis fail to respond to NSAIDs and colchicine, or there is a build-up of fluid inside the pericardium, which could put the heart at risk.

Corticosteroids block the effects of the immune system, leading to a reduction in inflammation.

Corticosteroids are powerful medicines and can have a range of side effects, especially if used for a long period of time.

Side effects of corticosteroids include:

  • weight gain
  • thinning of the skin
  • mood swings
  • increased sweating
  • increased vulnerability to infection

Recurring pericarditis

NSAIDs can be used to relieve symptoms of an episode of pericarditis, while a long-term course of colchicine has proved effective in preventing the return of symptoms.

If medications fail to control symptoms then a short-course of steroid medication may be recommended.

If your symptoms are particularly severe and are not responding to medication, then a type of surgery known as pericardiectomy may be recommended.

This involves the surgeon making a large incision in your chest and removing some or all of your pericardium.

It should be stressed that a pericardiectomy is usually regarded as a last resort, as the surgery is relatively risky – there is an estimated 1 in 20 chance of it causing death.

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Chronic pericarditis

Chronic pericarditis is defined as pericarditis that persists for more than three months.

There are two main types of chronic pericarditis:

  • chronic effusive pericarditis – when an excess amount of fluid gathers in the space inside the pericardium
  • chronic constrictive pericarditis – where the tissue of the pericardium becomes hardened through scarring

Chronic effusive pericarditis

It is hard to estimate exactly how widespread chronic effusive pericarditis is as most cases do not cause any noticeable symptoms. One study estimated that 1 in 20 older adults have some degree of effusion (build-up of fluid) inside their pericardium.

In cases where symptoms are present, they may include:

  • chest pain
  • light-headedness
  • cough
  • shortness of breath
  • hiccups

Possible causes of chronic effusive pericarditis include:

  • infections, such as hepatitis or tuberculosis
  • cancers that spread from other parts of the body to the pericardium
  • damage or injury that occurs during surgery

However, in many cases no obvious cause can found.

Medications such as non-steroidal anti-inflammatory drugs (NSAIDs) are the first treatment to try.

If medication fails to be effective, surgery may be recommended. Chronic effusive pericarditis can be treated with a surgical technique called a pericardiocentesis.

During a pericardiocentesis, a thin plastic tube known as a catheter will be passed through the chest and guided into the pericardium. Imaging technology, such as an echocardiogram, may be used to guide the catheter with accuracy. The catheter then drains away the excess fluid. A local anaesthetic is is used to numb the skin of your chest so you will not feel any pain during the procedure.

Chronic constructive pericarditis

It is estimated that 1 in 10 people with a history of acute pericarditis will go on to develop chronic constructive pericarditis.

The most common symptom of chronic constructive pericarditis is shortness of breath.

Other symptoms include:

  • fatigue
  • abdominal pain and swelling
  • nausea
  • vomiting

Possible causes of chronic constructive pericarditis include:

  • infections – such as tuberculosis
  • complications of radiotherapy
  • damage or injury that occurs during surgery

However, in most cases no obvious cause can be found.

Unlike the acute form of pericarditis, chronic constructive pericarditis tends not to respond well to medication and usually the only realistic option for a complete cure is to surgically remove the pericardium (pericardiectomy).

However, this type of surgery carries a 1 in 20 risk of causing death, so surgery would only usually be recommended if your symptoms were having a significant adverse effect on your quality of life.

Cardiac tamponade

In a small number of cases, inflammation of the pericardium can lead to a large build-up of fluid inside the pericardium. The extra fluid puts the heart under pressure, which makes it unable to pump blood around the body as effectively as normal. This is known as cardiac tamponade.

Cardiac tamponade is a potential complication in all cases of pericarditis, but it is more common in cases where pericarditis has been caused by tuberculosis or cancer.

If the heart cannot pump blood at the normal level, blood pressure can drop rapidly and cause:

  • light-headedness
  • blurred vision
  • palpitations
  • confusion
  • nausea
  • general weakness
  • a temporary loss of consciousness

Cardiac tamponade is life threatening and requires emergency treatment. If you have a history of pericarditis and develop the symptoms listed above, call 999 and ask for an ambulance.

Cardiac tamponade is usually treated with a pericardiocentesis, as mentioned above.

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