An unqualified comment, but I have just been reading about the development of a minute ultrasound device that can scan inside the ( typically 3mm ) vessels supplying the heart.
Remember that an encouraging angiogram is not a certificate of good health.
http://en.wikipedia.org/wiki/Angiogram
This wonderful system, along with the miraculous engineering of devices to hold open blocked vessels, has given a lot of people a reprieve. However, new findings seem to spell out more clearly than ever, the importance of not allowing the build-up of the ‘wrong cholesterol' in the first place.
It seems that it can become imbedded in the artery walls, yet leave them appearing open on the angiogram. Inflamation starts because of the very cells that should be protecting us, and the bursting out of these warring entities is sudden and often catastrophic.
the study of inflamation has gone into top gear in the last decade and with some surprising results. In this case they made the clear statement that an inflamed heart is for life.
If you are likely to be affected, I would advise putting your total effort into counter-measures, even to going onto a diet that resembles the UK in wartime.