I personally don't know too much about oral chelation therapy.

However, it is complex, and not easy to understand.

What I did find was this:
http://www.chelationtherapyonline.com/articles/p113.htm

In this article it is stated that only about 5% of EDTA is absorbed. The rest remains in the GI tract.

Many things can cause heart burn. Even simple ginger can reflux if taken improperly.
Many drugs do too (Fosamax, Actonel are examples).

Since EDTA requires many pills to get any effect, you are swallowing alot of EDTA. Solutions would be to space them out...and take with a full glass of water--not on a full stomach. DO NOT LIE DOWN, and remain upright for at least an hour or two.
This is a good monograph, but does not discuss oral:
http://www.umm.edu/altmed/ConsSupple...cidEDTAcs.html

Many oral forms are the calcium salt ..
Others are the di-potassium magnesium form mentioned in the first link above.

There is not great evidence that EDTA oral will fix any artery problem.
And there is evidence that it will create a chromium deficiency.
Oral EDTA does not affect zinc absorption, and was thought at one time to enhance it.
http://jn.nutrition.org/cgi/content/full/135/5/1102
(this is complex article with pros and cons).
But I would not expect severe losses of zinc from an oral EDTA since I could not find that to be definite in the literature.

Now, this chelating agent which is RX only is different:
http://www.rxlist.com/cgi/generic/succimer_cp.htm

If you have kidney stones composed of calcium oxalate (about 80% of patients), the best preventatives for that are 1) avoidance of oxalate in the diet (Google oxalate in foods) 2) use of calcium citrate --which actually prevents stones composed of calcium oxalate.
Stones composed of other substances, require other means, usually a solution of citrate to change the pH of the urine.

The oral chelation craze has paralleled the popularity of the book The Calcium Bomb. It is still controversial.

I also echo Chemar's and Ortho's suggestion to have medical supervision.
Continued heartburn can lead to esophageal erosions, damage, and serious
consequences.

Please be careful.