My experience with the same type of chest pain you have just describe, and after
undergoing the same test you have mentioned.  Between my family doctor and
myself discovered that it was cause by an imbalance of the thyroid gland.  Since
my doctor knows that (when at all possible) I refuse to take any PX. Medication,
he suggested that I take an Iodine supplement for fix the problem.  I am happy
to report that after taking the second Iodine supplement pill the pain went
away, needless to say I still take 1 Iodine supplement a day and have been pain
free ever since.

Hope this work for you too.

Good luck to you,

Clelia