Chapter 8: Abdominal Aortic Aneurysms

The following sections are included:

• An aneurysm is an abnormal dilatation of a vessel to greater than 50% normal size.

• Smoking, male gender, hypertension and genetics are the main risk factors for abdominal aortic aneurysm (AAA).

• The annual risk of rupture for an AAA of 5–5.9 cm is 5%.

• Contrast enhanced tomography (computed tomography, CT) is the gold standard for measuring the size of an aneurysm and planning intervention.

• The UK small aneurysm trial (UKSAT) helped reach a consensus about the minimal size at which aneurysms should be treated — usually 5.5 cm in the UK.

• The UK endovascular aneurysm repair trial (EVAR) 1 showed better early results for EVAR vs. open surgery, although after 2 years there was no benefit and at 15 years EVAR was inferior.

• The UK EVAR 2 trial in unfit patients showed no difference between endovascular and open repair in unfit patients.

• The IMPROVE, AJAX and the ECAR trials showed similar mortality for endovascular vs. open repair for ruptured aortic aneurysms.