I had a bypass op after angina.My LAD was blocked, and I think that makes me fairly typical.After the op I was hoping I'd be twenty years younger but I was disappointed - I was pretty much the same as pre op, so my view of the science involved is not high, but that's just my doctor prejudice.
Anyway people like me are always googling how to reverse plaque, how to undo athercerosis etc. and finding either you can't or a plant based diet has some claims but even that is disputed.
So lets say the accepted science is that nothing can reverse it- although it is true that reversal has been achieved by some individuals .Mostly the experts say the best you can do is to stabilise and therefore statins, exercise and sensible diet are suggested.
The worst bit of info for me, being a believer in exercise, is that healthy runner types with a lot of miles on the clock have even more plaque than their equivilant sedentary cohort. That's not in the least bit fair.
Which brings me to these breath books.Ones by James Nestor, and the other is by an oxygen advantage guy.These same two also have YouTube videos.
The main bit of science is that there is something called the Bohr effect.Oxygen can only be released by haemoglobin if there is carbon dioxide. And because we over breath we don't have this co2.
Once you get back some of this Co2 a whole cascade of physiological things take place.I strongly advise anyone with some kind of heart problem to take a look at this.
PS. I did not mention Wim Hof and deliberately exclude his method.