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Pulmonary embolism (PE)

Tepenga ia-aurkai anō

Blood clot travels up a vein into the lungs, where it blocks an arteryA pulmonary embolism (also known as a PE) is a very serious medical emergency. It's a blockage in one of the arteries (blood vessels) in your lungs, usually caused by a blood clot. The most common cause of a PE is a deep vein thrombosis (DVT), a clot in one of your legs.

Symptoms of a PE

You can have different symptoms depending on how big the clot is and where in the lung it goes to. Small PEs do not always cause symptoms.

Symptoms include:


Because a PE is very serious, if you have any symptoms of a PE, especially if you have one or more risk factors, get immediate medical assistance – call an ambulance on 111.

You may have an increased risk of having a PE for several reasons, including some medical conditions and long-distance travel.

See Reducing your risk of DVT or PE for information about the risk factors and how to reduce your risk.

Diagnosing a PE

Your doctor will assess all your symptoms and risk factors and decide how likely it is that you have a PE.

If you're at risk of having a PE, you'll need a CT scan of your lung (a special type of X-ray that shows pictures of structures inside your body) or a ventilation-perfusion lung scan (a special test that shows how much blood is getting into your lungs).

You may also need other tests including blood tests, an ECG (heart tracing) and a chest X-ray.

Treating a PE

Blood thinning (anticoagulant) medicines are used to stop the clot from getting bigger and new clots from forming. You may have injections for a few days before continuing on anticoagulant tablets. There are two types of tablets:

How long you'll need to take blood thinning medication will vary depending on the cause of your PE and your risk factors. You may need to stay on treatment for life.

If you have a severe PE, medication is sometimes used to dissolve the clot. Very rarely, the clot may be removed by surgery, or a filter may be placed in a vein to stop more clots moving to your lungs.

  HealthInfo recommends the following pages

On the next page: Reducing your risk of DVT or PE

Written by HealthInfo clinical advisers. Last reviewed February 2023.


See also:

Blood-thinning medicines for DVT and PE

Page reference: 49140

Review key: HIDVT-21919