What Causes Persistent Shortness Of Breath And Light Headedness Post Angioplasty?

A close friend of mine had coronary angioplasty last year at this time. I took him to the hospital and stayed with him for a couple weeks after the procedure... I m thinking it was for two coronary arteries occluded to a significant degree. My concern is his experiencing continuing shortness of breath problems ever since. He goes to the gym to exercise fairly regularly (2-3 times/week... on good weeks), but he s quite overweight for his age (70)... about 50 lbs over his bodyweight, atleast in the past. He s also had other complicating problems, including peptic ulcers which are still causing him to lose blood supply... apparently not healing as they should. He hasn t lost weight, which I know is a contributing factor, but I m wondering about the shortness of breath symptoms (lightheadedness too at times). shouldn t his Kaiser cardiologist be monitoring him closely still? What factors need to be considered further here? Any help or suggestions here would be greatly appreciated. Thank you. ... Steve Marvin