F F.
FYI, I've had a bypass (very young at the time for that sort of operation) and then 10 years later had angioplasty and the 10 years after that had another angioplasty. I would have no trepidation about having another angioplasty, if required, because it is fairly straight forward, done under local anaesthetic and produces very little discomfort afterwards. IME, they load you with Clopidogrel (an anti-platelet drug) at about 8 times the normal daily dose before the op and given that this takes time to get out of your system and the entry wound needs to heal, they (in my case, anyway) keep you in overnight to make sure that BP etc normalise and that the wound site isn't seeping. After a few days I was back at the gym and a week after that was back to my normal exercise levels with no associated pain and it has happily remained that way.
The by-pass took a while longer to recover from, in my case it was 5 weeks before I restarted any serious exercise, but was walking a couple of miles a day after about 4 to 5 days after the operation mainly to get the leg from where they had taken a length of "tubing" for the bypass graft working probably and to prevent any ancillary swelling. Don't know about the operation because that was under a general(!) but the chest was a bit bloody sore for a couple of weeks but that was a small price to pay.
Every time I've spoken to the medics involved they've said that the fitter you are, the better because it means that you've probably discovered the problem relatively early and the recovery period is much quicker. Another good reason to cycle a lot.
Good luck with it all.