An abdominal aortic aneurysm (AAA) is a bulging of the aorta, the body’s main blood vessel, which runs from the heart down through the chest and stomach. Prevalence of AAA in the population is high, up to nearly 13% depending on age group, particularly for men aged 65 and over. An AAA can get bigger over time and rupture, causing life-threatening bleeding. There is a high mortality rate of around 80% in patients with ruptured AAA; only dropping to around 50% when patients undergo surgery.