Gingernut: Thanks a lot for the info.
A few other pointers: I did have a sudden horrendous pain in the chest one day walking home from work about 3 years ago. It lasted a second...if that. It scared me of course but that was it! I played Tennis the same night, as i have done since, and had no probs!
I have also had the occasional "cramping" but this has not happened for a couple of years.
All of this has been told to the doc and he still said nothing is dramatically wrong and suggested it could be ventricullar problems which many people have, and live with, without being life threatening!
Cheers