i had (quadruple) coronary artery bypass surgery
I went in the hospital for a test, and they wouldn't let me leave the hospital till after the surgery.
so i didn't have much choice - also, not a lot of time to get worried.
they DID stop my heart.
Then they started it again.
all went well - optimum, even.
I can't give you a percentage, but i can tell you that if ANYTHING goes wrong with your heart or anything else in your body, being in a hospital, in an operating room, with cardiologists is the very best place to be if you want to survive.
maybe that's strange way to look at it, but it worked for me.,
BTW, did you hear that an early heart transplant patient just survived thirty years? he was one Of Dr. Christian Bernard's ( or is it Barnard's ?) patients. I think that is pretty good.
I know - not your exact surgery. But they have gotten pretty good at this. I am sure that your cardiologist would give you a low level tranquilizer to help through August, and they will give you more serious drugs in the hospital.