What is an aneurysm?
An aneurysm is a bulge in an artery or vein usually caused by a weakening of the blood vessel wall.
Aneurysms can be harmless. As long as they don't rupture (burst), they probably won't cause any problems.
However, sometimes aneurysms can burst because the vessel wall is weakened. This can be very dangerous, causing bleeding and even death.
If you think you might have an aneurysm, go to the nearest emergency department or call an ambulance on triple zero (000).
Aneurysms can occur anywhere. But there are two main types that are very serious — aortic aneurysms and brain aneurysms (also called cerebral aneurysms).
Aortic aneurysms occur in the aorta, which is the main artery that carries blood from the heart to the rest of the body. Brain aneurysms affect blood vessels in the brain.
Aneurysms can occur at any age but are more common in adults.
What are the symptoms of an aneurysm?
The symptoms of an aneurysm depend on where it is and whether it bleeds or bursts (ruptures).
Sometimes there is a small leak of blood from the aneurysm. This can cause:
- a sudden headache and nausea if it is in the brain
- a sudden pain in the abdomen (tummy) or back if it is in the abdomen
If the aneurysm bursts, it is very serious and can be fatal. If a brain aneurysm bursts, it can cause a sudden, very severe headache, nausea and vomiting. The person may become unconscious.
If an aortic aneurysms bursts, the person gets sudden pain in the back or belly and feels very weak. They may black out.
Sometimes a burst aneurysm in the brain can cause a stroke.
The main symptoms of stroke can be remembered by using the word 'FAST': Face-Arms-Speech-Time is critical.
Face — The face may have dropped on one side, the person may not be able to smile or their mouth or eye may have drooped.
Arms — The person with the suspected stroke may not be able to lift one or both arms and keep them there because of arm weakness or numbness.
Speech — Their speech may be slurred or garbled, or the person may not be able to talk at all despite appearing to be awake.
Time is critical — It is time to call triple zero (000) immediately to ask for an ambulance if you see any of these signs or symptoms.
CHECK YOUR SYMPTOMS — Use the Symptom Checker and find out if you need to seek medical help.
What causes an aneurysm?
Aneurysms can be congenital — that is, people can be born with them. They are more common in some families.
They are often due to a gradual weakening of the wall of an artery or vein. This can be due to high blood pressure, or high cholesterol levels, or smoking. An aneurysm can be caused by an accident or injury that damages the artery or vein such as a head injury.
They can also occur with certain medical conditions such as hardening of the arteries (atherosclerosis) polycystic kidney disease and some connective tissue disorders.
Using stimulant drugs like cocaine can also cause a brain aneurysm.
How are aneurysms treated?
If you have an aneurysm, you will need to have regular check-ups to monitor its size and your health. Usually, small aneurysms have a very small risk of bursting so your doctor will just check you regularly.
If the aneurysm grows, bursts or your doctor thinks it's likely to burst, you may need to have surgery. This involves clipping the aneurysm to prevent blood from reaching it, or inserting a tube through your groin to treat the aneurysm.
If the aneurysm causes bleeding on the brain, you will need emergency treatment in hospital.
If you have an aneurysm, your doctor may discuss ways you can prevent it from bursting. These include stopping smoking, treating high blood pressure if you have it, not lifting heavy weights, and cutting down on alcohol.
FIND A HEALTH SERVICE — The Service Finder can help you find doctors, pharmacies, hospitals and other health services.
ASK YOUR DOCTOR — Preparing for an appointment? Use the Question Builder for general tips on what to ask your GP or specialist.
Learn more here about the development and quality assurance of healthdirect content.
Last reviewed: September 2020