Sometimes called AAA - it is a weakening in the aortas wall, which is causing a ballooning, which causes more weakening of the artery wall.... 10 years ago they watched it and wouldn t usually do surgery until it was 5-6cm. which seems huge. but that is when your survival rate drops to 50-50 and the surgery of the day was a 50-50 chance. now i think there is a easier surgery and maybe could be done when it is smaller. If it would burst, you will be dead before you hit the floor, but odds are with you. they are hereditary - my mom, aunt had one and mom had an aneurysm in her brain as well - she survived the busting of that one, must have been a small leak or small vessel.