Things I have learnt so far about AAAs

There are 6 books related to my project piled up on my desk at the moment. I spent about an hour in the main library yesterday. Today I spent about 3 hours in the medical library and another hour in the main library. I've found out quite a bit about aneurysms.

Off the top of my head I can inform anyone who might ask that aneurysms generally occur on the aorta (the main artery going from the heart that feeds oxygen and other good stuff to the body) and that they occur far more commonly in the abdominal region than in the thoracic region although they can form in both places at the same time.

When aneurysms form on the abdominal aorta they generally occur just below the renal arteries (arterial branches that feed the kidneys). There are several different types of aneurysm, but the fusiform type is the one which occurs most commonly in the abdominal aorta. Fusiform aneurysms are where the artery gets gradually wider and then thinner again rather than suddenly ballooning out on one side which would be a saccular aneurysm.

Abdominal aortic aneurysms are most likely to rupture once they reach a diameter of 6cm, but they can grow bigger in some cases. Then again, in other cases an abdominal aneurysm may rupture before it reaches a diameter of 6cm. 0.3% of ruptured abdominal aortic aneurysms occur when the aneurysm is less than 4cm in diameter though. The "normal" diameter of the aorta in the abdomen ranges from about 1.5cm to about 2.1cm. That depends on gender and a few other factors.

In general 3% of people get aneurysms, but if your parent has an aneurysm you are far more likely to develop an aneurysm than someone who is not related to anyone with an aneurysm.

The problem with abdominal aneurysms is that they rarely present with any symptoms at all. Most people who have them will not know about them unless they are screened. The problem with screening is that the most effective and most useful screening method is computed tomography (CT), which is rather expensive and a little time-consuming. It is debatable (and people are debating it) whether or not it is worth the money it would cost to screen all people who may be "at risk".

Generally it is older people (over 50) who develop aneurysms. Men are most at risk of developing an aneurysm, but females are more at risk of rupture according to many studies.