Mental strength. A Positive attitude. Will.
You either have these qualities, or you better get them real quick. If you've been diagnosed with an aortic aneurysm, it's nearly inevitable that at some point you are going to need major open heart surgery to correct it. The influence of the qualities above on your quality of life and recovery are of utmost importance. Biology of Belief is a scientifically proven fact. If you bury your head in the sand and become depressed, your healing abilities at the cellular level become compromised. Even your immune system can be affected.
If you tend to be a not so positive person, get a new attitude and prepare to make drastic changes in your moods, outlook, and determination. You'll need to dig deeper than you ever have, but if a vietnam POW can find things to hang onto for 10 years in captivity so can you. Find something positive in every situation and cling to it. It's one thing to make it through open heart surgery, but having a positive attitude and being strong and diligent mentally is what's going to let you "live". Any blessing of additional time the doctor gives you on earth by fixing your aneurysm should be lived to the fullest extent. Taking up space is not good enough. What's the point in having a second chance if you're not going to LIVE, feel deeply, do new things, and find the silver lining in every cloud? Use this condition you've been diagnosed with to change your life and turn it into a positive for yourself and those around you.