Aneurysm
What is an aneurysm?
Aneurysm is the word used to describe a swelling that occurs in an artery or vein when its wall is weakened. This happens to blood vessels in the same way that the tyre of a motor car may show a bulge at a weak point.
Aneurysms can form in the blood vessels in almost any part of the body and they can have serious consequences.
Areas most likely to be affected are the brain, and the main artery that leaves the heart — the aorta. There are several reasons why some people develop aneurysms. They may be present at birth (congenital aneurysm). This is often the case with aneurysms affecting the blood vessels in the brain, which may not cause trouble for many years. Other causes include high blood pressure and narrowing of the arteries (arteriosclerosis).
Complications and treatment
The greatest danger from an aneurysm is that it may rupture (burst). This may happen after many years of increasing pressure and thinning of the wall of the affected blood vessel, rather like a balloon that is over-inflated. When this happens there will be bleeding which may cause a stroke if it happens in the brain, or dramatic collapse and sudden death if an aneurysm of the aorta ruptures. Sometimes the aneurysm will leak small amounts of blood, rather than bursting. This may cause severe headache or abdominal and back pains when the aorta is affected.
Sometimes aneurysms of the lower aorta may be noticed as a swelling in the stomach that can be felt to have a pulse. This can be confirmed by using an ultrasound. Surgical treatment is possible, removing the affected part of the aorta and replacing it with an artificial pipe. It’s also possible to insert an artificial pipe, or graft, at the site of the aneurysm to reinforce the weakened section and prevent the aneurysm from rupturing.
Aortic aneurysms can run in families and those with a close relative who has had this problem may need to have an ultrasound to check for this condition.
The average diameter of the aorta is 20 millimetres. If an aneurysm is seen it may require close watching with regular ultrasounds. If it is swelling quickly, or reaches a diameter of 55 mm, surgery is indicated, which may be life-saving.
Last Reviewed: 19 November 2009
- 1. National Heart Lung and Blood Institute [website]. Aneurysm (updated 2009, Apr). Available from: http://www.nhlbi.nih.gov/health/dci/Diseases/arm/arm_what.html (accessed 2009, Nov 20)
