Update
After seven hours of surgery, my Dad is in ICU and recovering. It's still too early to predict anything, but the surgical team said that it went pretty well. We are very lucky, the aortic aneurysm could have burst at anytime and would have meant almost certain death. I can't thank the radiologist who caught the problem while reviewing the x-rays, and the surgical team at the CHU in Sherbrooke for moving so quickly. He's awake this morning, but just in and out. It's going to be a long recovery. Thank you to everyone for your positive mental vibes :-)