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Pericardial Effusion

Written by Ada’s Medical Knowledge Team

Updated on

What is pericardial effusion?

Pericardial effusion is a buildup of fluid around the heart muscle. The heart is surrounded by a protective membrane called the pericardium, which is a sac comprised of two layers of tissue with lubricating fluid in between. Pericardial effusion occurs when the amount of fluid between the two pericardium (sac) layers is abnormally high. 1 2 3

Good to know: Effusion is the medical term for a buildup of fluid. Effusions can occur in other parts of the body besides the heart membrane. For example, fluid can build up around the lungs; this is called pleural effusion.

Often, pericardial effusion is mild, progresses slowly, does not cause any signs or symptoms, and is discovered incidentally as part of a routine medical check-up. However, if the pericardial effusion develops or progresses rapidly, the pressure it exerts may compromise the functioning of the heart and lead to serious complications, particularly where there is a large amount of fluid.

Signs of pericardial effusion may include: 1 2 3

  • Chest pain
  • Rapid heartbeat
  • Feeling lightheaded
  • Fainting

Pericardial effusion can be caused by almost any disease or health condition that affects the pericardium, including: 1 4

While pericardial effusion can affect people of all ages, the incidence seems to be higher in those over 50. 5 Generally speaking, in younger people the heart is better able to compensate for a progressing effusion. 2

The prognosis for pericardial effusion depends on the size of the effusion and the underlying cause. Small effusions are quite common and may simply require monitoring by a doctor, often resolving on their own with supportive treatment. 1

Where necessary, treatment for pericardial effusion involves addressing the cause, for example by prescribing antibiotics for a bacterial infection, steroids and other medications for rheumatoid arthritis, or anti-inflammatory medications for pericarditis. 1 6 Large effusions typically indicate a more serious health condition and may require drainage (pericardiocentesis). ref1 7 Recovery may take several weeks or months, depending on the severity and cause of the pericardial effusion. ref6

A possible complication of pericardial effusion is cardiac tamponade, which is a medical emergency requiring immediate intervention. 1

Signs and symptoms of pericardial effusion

Signs and symptoms depend on the size of the heart effusion and the rate at which it develops. People with small pericardial effusions that have developed slowly may not experience any specific symptoms at all. 1 However, there may be symptoms related to the underlying cause, for example, fever from pericarditis.

Where present, symptoms of pericardial effusion may include: 1 8

  • Feeling light-headed or fainting
  • Palpitations
  • Rapid heartbeat (tachycardia)
  • Shortness of breath or difficulty breathing
  • Chest pain, pressure or discomfort. This symptom may be worse when lying flat on the back, and relieved by sitting up and leaning forward
  • Cough
  • Difficulty swallowing
  • Hoarseness
  • Anxiety and confusion
  • Hiccups
  • Nausea and vomiting
  • Feeling of fullness in the abdomen
  • Abdominal distension (bloating)


A wide range of health conditions can cause pericardial effusion. Possible causes include the following: 1 9

In many cases of pericardial effusion the cause of the fluid buildup is unknown. This is called idiopathic pericardial effusion.

Diagnosing pericardial effusion

The first step in diagnosing pericardial effusion will be for a doctor to take the affected person’s medical history and perform a physical examination. The doctor will typically measure the individual’s blood pressure, and pulse, and listen to the heart through a stethoscope for audible signs of fluid buildup. 1 9

Where the pericardial effusion has developed slowly, symptoms may be absent or minimal. A doctor will usually look for the following:

  • Accelerated pulse
  • Low blood pressure
  • Muted heartbeat (through the stethoscope)

The doctor will also look for possible signs of chronic heart failure, including:

  • General physical weakness
  • Distended jugular veins (in the neck)
  • Fast or labored (difficult) breathing
  • Buildup of fluid in the abdomen (belly)
  • Swollen legs

Rapid development of low blood pressure, muted heart sounds and distended jugular veins may indicate the life-threatening condition of cardiac tamponade. 1 9

It is likely that the doctor will request further tests, such as an ECG (electrocardiogram) or ultrasound, to confirm the diagnosis of pericardial effusion and establish the cause. Tests may include: 1 9

  • Blood tests: These can identify infections, autoimmune conditions, thyroid dysfunction, kidney failure and other possible underlying causes of pericardial effusion.
  • Echocardiogram: A heart ultrasound scan or echo will show the size and shape of the heart and whether fluid has accumulated in the pericardium. This type of scan, which is widely available, is particularly important in the diagnosis of pericardial effusion.
  • Electrocardiography (ECG or EKG): An ECG is a test that measures the heart’s electrical activity. Pericardial effusion may cause abnormal patterns to show on an ECG.
  • Chest X-ray: The heart may appear enlarged where there is significant pericardial effusion. It may have a “water bottle” shape.
  • CT or MRI scan: Computed tomography (CT) and magnetic resonance imaging (MRI) tests may present a clearer picture of the presence and size of pericardial effusion.
  • Pericardiocentesis: Removal of a small amount of fluid from the pericardium, using a needle, allows for testing for infections (e.g, tuberculosis) and tumor markers.

In addition, the doctor may ask for a pericardial biopsy to be performed. 1 In this procedure, a small amount of tissue is removed from the pericardium to test for infection and other possible causes of pericardial effusion. 10

How is pericardial effusion treated?

Treatment of pericardial effusion depends on the cause and severity of the condition. In some cases where the effusion is small and uncomplicated, it may resolve on its own, with anti-inflammatory medication recommended to help the healing process. 11

Treatment approaches may include: 1 2 12

Strategies to reduce symptoms: These include:

  • Oxygen therapy where circulation is compromised
  • Diuretics (water pills)
  • Other heart failure medication

Strategies to treat complications: These include pericardiocentesis where cardiac tamponade is present

Strategies to identify and treat the underlying condition: These include:

  • Pericardiocentesis, pericardial biopsy, antibiotics where a bacterial infection is present
  • Steroids and other medications where rheumatoid arthritis is implicated
  • Chemotherapy, radiation therapy and other treatments where cancer is the cause

In some cases, surgical treatment may be necessary.

Treating pericarditis (inflammation of the pericardium)

If pericarditis is present, treatment may include NSAIDs and, in certain cases, a course of colchicine – another type of medication that reduces inflammation. Colchicine may improve the prognosis and help prevent pericarditis recurring. If the pericarditis does not respond to treatment, a course of corticosteroids, such as prednisone, may be necessary. 13 14 15 In cases of acute pericarditis caused by myocardial infarction (heart attack), however, corticosteroids cannot be used, as they may negatively affect the healing process. 16

Read more about pericarditis treatment »


Large effusions that persist or are at risk of causing cardiac tamponade may be treated with pericardiocentesis. In this procedure, excess fluid is drained from the pericardium using a needle and catheter (thin tube). The doctor will typically rely on echocardiography (ultrasound) to guide the process. 1 4 8 12


Where the pericardial effusion is very large and repeated pericardiocentesis has not been effective, surgery may be recommended. The following procedures may be used:

Subxiphoid pericardiostomy: Also called a “pericardial window”, this procedure can be performed under local anesthesia and has a high success rate. The doctor will make an incision under the breastbone and remove a small part of the pericardium to drain the excess fluid. 1 8

Video-assisted thoracoscopic surgery: This is also known as VATS or thoracoscopy. Although the procedure involves general anesthesia, it is minimally invasive, requiring only small incisions in the chest wall. The doctor will use a tiny camera to view the pericardium and make a more accurate diagnosis, and can then drain excess fluid by creating a small hole in the pericardium (pleuropericardial window). 17 18

Alternatives to surgery

Where surgery is not recommended, the following interventions may be used:

Percutaneous balloon pericardiotomy: During this procedure, a doctor inserts a needle into the pericardium via the chest wall. The needle is then replaced with a catheter, which has an inflatable balloon at the tip. This balloon is inflated to create a small hole in the pericardium through which excess fluid can be drained. Balloon pericardiotomy is predominantly used for repeated pericardial effusion that is caused by cancer. 1 8 19

Intrapericardial sclerosis: In this procedure, a medication is administered to the pericardium to treat the effusion. Medications used include the antibiotics tetracycline and doxycycline and the chemotherapy drug cisplatin, among others. 1


Complications that can arise from pericardial effusion include cardiac tamponade, as well as large effusions that recur or persist for longer than six months.

Cardiac tamponade

This is a life-threatening condition that may develop from pericardial effusion. If the fluid exerts pressure on the heart to the extent that its pumping ability is compromised, immediate treatment is required to prevent mortality.

Symptoms of cardiac tamponade may develop rapidly (within minutes or hours) and can include:

  • Shortness of breath
  • Weakness and faintness
  • Nausea
  • Palpitations
  • Confusion or loss of consciousness
  • Blurred vision

If you think that you might have signs of cardiac tamponade, call emergency services immediately.

Cardiac tamponade is treated with emergency pericardiocentesis or surgery. In severe cases, cardiopulmonary resuscitation (CPR) may be required. 1 20 21

Chronic pericardial effusion

In some cases, large effusions may recur or persist for longer than six months and require ongoing medical treatment. 1 The affected individual may not experience any symptoms or problems. However, because pericardial effusion may lead to cardiac tamponade, going for regular check-ups and ensuring careful management of heart health is critical. The doctor may recommend pericardiocentesis to drain the cardiac effusion as a preventative measure. 6 In many cases, however, pericardiocentesis alone may prove inadequate, and a pericardiectomy may also be necessary. 2

Good to know: Small pericardial effusions that persist for a long period of time are fairly common, and are not as much of a concern as large effusions.

Other names for pericardial effusion

  • Fluid around the heart


Q: What causes fluid around the heart?
A: Pericardial effusion can be caused by many different conditions that affect the membrane of the heart, resulting in pericarditis. These include:

In many cases, the cause of pericardial effusion is unknown.

Q: Is pericardial effusion serious?
A: Pericardial effusion can be serious. Many cases are mild and do not cause any symptoms or long-term health problems, but some cases,particularly those that develop rapidly and involve a large buildup of fluid, can lead to life-threatening complications such as cardiac tamponade. If you think that you might have signs of pericardial effusion, it is recommended that you contact a doctor without delay.

Q: Can pericardial effusion return?
A: Yes, pericardial effusion can recur. Many cases clear up and do not come back, but in some cases chronic pericardial effusion may develop. See the section on chronic pericardial effusion above for more details.

Q: Pericardial effusion vs. cardiac tamponade – what is the difference?
A: Pericardial effusion is the term for an accumulation of fluid around the heart. The amount of fluid may be small or large, and the condition is not always serious or life-threatening. Cardiac tamponade is a rare but life-threatening possible complication of pericardial effusion and other heart conditions. Cardiac tamponade is when fluid exerts pressure on the heart, impeding its ability to pump and sometimes leading to cardiac arrest. Cardiac tamponade may develop very quickly and requires emergency treatment to prevent mortality. 1 22

Q: Pericardial effusion vs. pericarditis - what is the difference?
A: Pericardial effusion is the term for a buildup of fluid around the heart. The membrane around the heart is called the pericardium; this is a sac made up of two layers of tissue with lubricating fluid in the middle. If this fluid increases beyond normal levels, it is called pericardial effusion. Pericarditis is the term for inflammation of the pericardium. Pericarditis can cause pericardial effusion.

Read more about Pericarditis »

Q: Pericardial effusion vs. pleural effusion - what is the difference?
A: Pericardial effusion is the term for a buildup of fluid around the heart. Pleural effusion is the term for a buildup of fluid around the lungs, or, more accurately, in the space between the lungs and the chest cavity. 23

Q: Is there a connection between pericardial effusion and cancer?
A: Yes. Cancer may be a cause of pericardial effusion where it has spread to the pericardium. These cases of pericardial effusion are very serious and require urgent medical treatment. 12 The types of cancer that most commonly cause pericardial effusion include: 24

Q: Can pericardial effusion be prevented?
A: It is not usually possible to prevent pericardial effusion. However, steps can be taken to prevent the condition becoming more serious or developing into cardiac tamponade. These steps include: 25

  • Seeking treatment without delay
  • Following the treatment plan (for example, taking medications as prescribed)
  • Listening to a doctor’s advice for ongoing medical care