My father is 71 years old and he has just been on an operation for implantation of drug releasing stents. His heart arteries were 70% obstructed because of the arteriosclerosis (caused by a lot of junk food) and the operation was necessary. I am just afraid that he will not be able to change his life and that restenosis will follow some time after.
And you have a good reason to be worried. Restenosis could be easily needed because of the arteriosclerosis that might attack again and this time it will be even easier because of the stents. So you have to persuade him to change his eating habits, there are diets that will make him full and still not raise his cholesterol level. I know that it will be difficult because of his age, but if he wants no more health problems, that is something he has to do.