Abdominal aortic aneurysm

An abdominal aortic aneurysm (AAA) is a swelling (aneurysm) of the aorta. The aorta is the main blood vessel that supplies blood to your body. An AAA can be dangerous if it isn't spotted early on. Men aged 65 and over are most at risk of AAAs.

About an AAA 

The abdominal aorta is the largest blood vessel in the body. It runs from your heart down through your chest and abdomen (belly). 

The bulging or swelling occurs when the wall of the aorta weakens. AAAs are most common in men aged over 65. This is why all men in Northern Ireland are invited for a screening test when they turn 65 (see screening below).

Symptoms of an AAA 

AAAs don't usually cause any obvious symptoms. They are often only picked up during screening or tests carried out for another reason.

Some people with an AAA have:

  • a pulsing sensation in the tummy (like a heartbeat)
  • tummy pain that doesn't go away
  • lower back pain that doesn't go away

If an AAA bursts, it can cause:

When to get medical help 

Call 999 for an ambulance immediately if you or someone else develops symptoms of a burst AAA.

If you have symptoms of an AAA that has not burst, make an appointment to see your GP as soon as possible, especially if you're at a higher risk of an AAA.

An ultrasound scan of your tummy may be done to check if you have an AAA.

Who's at risk of an AAA 

An AAA can form if the sides of the aorta weaken and balloon outwards. It's not always clear why this happens, but there are things that increase the risk.

People at a higher risk of getting an AAA include:

  • men aged 65 or over – AAAs are up to six times more common in men than women, and the risk of getting one goes up as you get older
  • people who smoke – if you smoke or used to smoke, you're up to 15 times more likely to get an AAA
  • people with high blood pressure – high blood pressure can double your risk of getting an AAA
  • people with a parent, sibling or child with an AAA – you're about four times more likely to get an AAA if a close relative has had one

Speak to your GP if you're worried you may be at risk of an AAA. They may suggest having a scan to check if you have one and making healthy lifestyle changes to reduce your risk of an AAA.

Treatments for an AAA 

The recommended treatment for an AAA depends on how big it is.

Treatment isn't always needed straight away if the risk of an AAA bursting is low.

Treatment for a:

  • small AAA (3cm to 4.4cm across) – ultrasound scans are recommended every year to check if it's getting bigger; you'll be advised about healthy lifestyle changes to help stop it growing
  • medium AAA (4.5cm to 5.4cm) – ultrasound scans are recommended every three months to check if it's getting bigger; you'll also be advised about healthy lifestyle changes
  • large AAA (5.5cm or more) – surgery to stop it getting bigger or bursting is usually recommended

Ask your doctor if you're not sure what size your AAA is.

Reducing your risk of an AAA

There are several things you can do to reduce your chances of getting an AAA or help stop one getting bigger.

These include:

If you have a condition that increases your risk of an AAA, such as high blood pressure, your GP may also recommend taking tablets to treat this.

Screening for an AAA 

All men in Northern Ireland are invited for screening in the year they turn 65 to check if they have an AAA.

Men who are over 65 and have not been screened can ask for an appointment by contacting the screening programme office. Women and men under 65 are not invited for screening.

If you feel you have an increased risk of having an AAA, talk to your GP who can still refer you for a scan.

The information on this page has been adapted from original content from the NHS website.

For further information see terms and conditions.

This page was reviewed January 2019

This page is due for review November 2020

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