I haven't talked about it much on Texags but I had a triple bypass 2 years ago in April.
I had 100% blockage in 2 arteries and 70% in the third. Surprisingly I had gone skiing 3 weeks before and did ok. Was having a lot of trouble on my daily walks and we knew something was very wrong. Turns out I had genetically tiny heart arteries.
So here is what to expect.
It f'ing hurts. He will wake up in pain and won't be able to sleep at all for days. I think I went a week before I slept more than an hour in a night. I was also hot. Very hot, like I thought I was going to die from heat. When he is in ICU he may want a fan. He won't be able to talk or write. The first 3-4 days are bad. It is hard to breathe. Your lungs are deflated for an hour or so so he will have about 1/4 the lung power of normal. Use that spirometer, which of course also hurts and makes you cough, which is bad.
Brain fog is real. Your heart is a dead empty sack for a long time and no matter what they do, he will lose memories forever and will not be as smart afterwards. After 6 months or so it will start coming back but some things will just be lost forever.
Take the chest precautions seriously. I had a bad cold a couple months after and rebroke my sternum just from coughing. So I had to have a second open heart surgery to bolt that stuff back together. It didn't hurt when the sternum bones moved but they moved all over the place and if it got infected I would have died, so we put in a bunch of plates, wires, and screws. See if the surgeon will do the plates the first time, otherwise he can break it by sneezing and when the cables dig into your sternum it hurts. Do not do the Robichaud procedure or whatever they call it. It is just extra wires and won't help. Titanium plates are the solution, see if they will do it right from the start.
The old people do better than the active ones because they will wait out the healing. I was out shoveling snow and riding a mountain bike. Don't do that, just sit in bed and let it heal. Walking is his friemd
He will most likely survive it, but it is bad. They told me I had a 4% chance of never waking up and a 10% chance of not surviving a month.
Long term... It is now 2 years later and I am back to hard mountain biking, skiing blacks, and kinda lifting weights. You will never lift again but I can do 25 pound kettlebell routines all day and they work. I'm not as smart as I was before the surgery and I don't have time for idiots at all. I went through a few months where I was easy to anger, but that has passed. Hardest thing is remembering names from people I knew back in high school and stuff. If someone says their name I know who they are, but if they talk about a person doing something it is gone until someone says the name. Brain fog is real