Why and when would we want to would want to bind a metal?
Per Wikipedia:
"…Chelation therapy is the use of chelating agents to detoxify poisonous metal agents such as mercury, arsenic, and lead by converting them to a chemically inert form that can be excreted without further interaction with the body…"
So chelation is used primarily to bind and remove toxic metals located throughout the body
**_But what toxic metals or minerals is this chelation process supposed to remove to fight coronary disease?_**
_That is unclear_, the clinical trial of the TACT study says [2,3]:
"…EDTA chelation therapy involves repeated administrations of a synthetic amino acid to reduce _atherosclerotic plaque and other mineral deposits_ throughout the cardiovascular system…'
The plaque component with metal properties is the extracellular_** calcium**_ deposits between the muscular wall and outer portion of the plaques. So Calcium seems the primary removal target.
Sure enough, an article in biomedcentral [2] has : "…calcium chelation resulting in dissolution of atheromatous plaques, free radical scavenging action, reduction of total body iron stores, cell membrane stabilization, arterial dilatation due to calcium channel blocking action, improvement of arterial wall elasticity and increased production of nitric oxid…"
_**The problem is that the chelation of calcium is not an easy process: "**_…the inability of EDTA, a water soluble compound, to effectively complex with plaque calcium…
But more minerals are gathered (chelated) besides calcium:
"…Calcium disodium EDTA chelation _**removes heavy metals and minerals from the blood, such as lead, iron, copper, and calcium,** _and is approved by the U.S. Food and Drug Administration (FDA) for use in treating lead poisoning and toxicity from other heavy metals. Rather than testing calcium disodium EDTA, TACT used another salt, disodium EDTA, under an FDA license as an investigational new drug (IND). Although disodium EDTA is not approved by the FDA to treat CHD, some physicians and alternative medicine practitioners have recommended its use in chelation as a way to treat CHD…"
**_Here lies the main issues: iron, copper, and calcium are not necessarily bad forthe body._**
As a matter of fact, _**not enough iron is called anemia!**_ Other risks of chelation therapy are also serious:
"…heart failure, a sudden drop in blood pressure, abnormally low calcium levels in the blood (hypocalcemia), permanent kidney damage, and bone marrow depression (meaning that blood cell counts fall)…"
_**Also, not enough calcium is called hypocalcemia and ** _can lead to convulsions, arrythmias, tetany and numbness/parasthesias (Wikipedia)
The figure below shows the EDTA compound binding a metal atom.
EDTA Chelation Of Metal Atom
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So before we remove indiscriminately metals and minerals from the body of a Cardiovascular Disease (CVD) patient, maybe we should know more about the relationship between those minerals and CVD .
But the chelation proponents argue that many other metals and minerals removable by chelation are bad for your heart. In fact, the British Medical Bulletin [5] adds cadmium and mercury to the list.
_**Essentially, heavy metal pollution is bad for you and your heart. Fine, but does that mean that most heart diseases are caused by such pollution?**_
That remains to be shown. Chelation seems like a dragnet removal of many metals from the CVD patient. Maybe future studies should discover a chelating agent specialized in removal of a specific metal, say, calcium.
Until then, you will note that the clinical trial described in [2]
"…A typical protocol might consist of 30 intravenously administered solutions of 3 grams of disodium EDTA _**with concomitant administration of varying levels of ascorbic acid, B-vitamins, heparin, and the minerals magnesium, copper, zinc, selenium and manganese** _delivered over 1.5 to 3 hours in 500 ml to 1000 ml of normal saline…"
The addition of minerals magnesium, copper, zinc, selenium and manganese is probably there to compensate for the removal of these essential metals from the patient's body.
Other medications, such as diuretics can bring about loss of electrolytes and can require mineral supplementation, but the mechanics of the use of diuretics and their efficacy is well understood.
_**Granted the latest results of the Trial to Assess Chelation Therapy (TACT)**_
_**discussed in [1] are intriguing. **_
Quoting [1] : "…The primary endpoint of the trial– the composite of death, MI, stroke, coronary revascularization, or hospitalization for angina– was significantly lowered in the chelation group: 26.5% in the chelation group versus 30% in the placebo group…"
But, although 26.5% is an improvement over than 30%, it is certainly not dramatic!
_**So let us look for more chelation studies confirming the benefits and shedding light on the processes, before jumping on the chelation bandwagon!**_
_**Sources:**_
1. [cardiobrief](http://cardiobrief.org/2012/11/04/nih-trial-gives-surprising-boost-to-chelation-therapy/) ; "NIH Trial Gives Surprising Boost To Chelation Therapy" ; Nov 2012
2. [biomedcentral](http://www.biomedcentral.com/1471-2261/5/32) ; "EDTA chelation therapy for cardiovascular disease: a systematic review" ;2005
3. [clinicaltrial.gov ](http://clinicaltrials.gov/show/NCT00044213) ; "Trial to Assess Chelation Therapy (TACT)" ; Oct 2012
4. [National Heart Lung and Blood Institute (NHLBI)](http://www.nhlbi.nih.gov/news/press-releases/supplement/questions-and-answers-the-nih-trial-of-edta-chelation-therapy-for-coronary-heart-disease.html) ; "Questions and Answers: The NIH Trial of EDTA Chelation Therapy for Coronary Heart Disease" ; 2012
5. [British Medical Bulletin](http://bmb.oxfordjournals.org/content/68/1/167.full) ; "Hazards of heavy metal contamination" ; 2003
](http://www.medinewsdigest.com/wp-content/uploads/2012/11/EDTA-Chelate-jpeg.jpg){kind=link}
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