Chelation

Written by: 
Richard Thomas, medical writer

Chelation, or chelation therapy, is a controversial medical procedure used in the treatment of cardiovascular disease (CVD).

The technique involves slowly feeding a special mix of chemicals into the bloodstream by means of an intravenous dripA means for the continuous injection into a vein.. This is intended to clean out harmful deposits in the body's arteries and thus prevent or reverse the effects of heart and bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. vessel - or cardiovascular - disease (CVD).

The process must be overseen by a registered medical doctor in a properly equipped facility and is known technically as 'chemo-endarterectomyThe removal of atherosclerotic plaque from the inner wall of an artery.'.  It usually involves extended treatment of four-hourly sessions once or twice a week spread over several weeks, sometimes with 'top up' treatments every few months afterwards.

What is it used for?

Clogging and hardening of the arteries responsible for delivering bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. to the heart - known as atherosclerosisDisease leading to fatty deposits in the inner walls of the arteries, which reduce and may eventually obstruct blood flow. - is the main cause of heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction. and stroke, as well as being the leading cause of premature death, in industrialised nations.

Atherosclerosis is widely labelled a 'disease of civilisation' as it is considered that a poor diet consisting mainly of processed fatty foods, along with lack of exercise, and stressRelating to injury or concern. - features of many so-called 'civilised' lifestyles - are all leading contributory factors in the development of the condition.

A wide range of treatments to reverse the disease has been developed over many decades, from medicines to open-heart surgery. Chelation (pronounced 'key-lay-shun') is one of the more specialist - and, to some, controversial - of these.

Why is it controversial?

Chelation is controversial because one of the usual key ingredients in the cocktail of chemicals used to flush out the arteries is a synthetic amino acidAn organic compound that is the basic building block of all proteins. known as ethylenediamine tetraacetic acid, or EDTA.

EDTA was originally developed in Germany in the early 20th century as a calciumAn element that forms the structure of bones and teeth and is essential to many of the body's functions. stain remover and high doses of it can damage the kidneys, among other reported problems. It became an accepted medical treatment for poisoning from heavy metalsMetals that can accumulate in the body, with a detrimental effect on health. such as lead, mercury and cadmium. More recently, it has been used in the treatment of cardiovascular disease (CVD).

Doctors developed the therapy for heart disease in the 1950s in the belief that if EDTA could 'claw' out heavy metalsMetals that can accumulate in the body, with a detrimental effect on health. from the bloodstream (the term 'chelate' comes from the Greek word for 'claw'), it could do the same in cardiovascular disease by dissolving the arterial 'plaques', or calcified fatty blockages, that build up in the body's bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. vessels.

Technically, though, the process is more one of binding than clawing: practitioners claim that EDTA binds harmful substances to itself before enabling them to be flushed away in the urine.

Chelation developed a wide following among health professionals in the latter half of the 20th century, particularly in North America, where more than 300 practitioners are now estimated to be treating some half a million patients.

But despite this, the therapy has still not been accepted by leading bodies such as the American Heart Association and the British Heart Foundation. Both claim EDTA not only removes calciumAn element that forms the structure of bones and teeth and is essential to many of the body's functions. from the body, making bones brittle, but also depletes important minerals such as zinc and magnesium.

Supporters, however, among them the late eminent scientist Linus Pauling, argue that chelation with EDTA removes calciumAn element that forms the structure of bones and teeth and is essential to many of the body's functions. from plaques, not bones, and that supplementing treatment with vitamin and minerals replaces any nutrients lost in chelation.

The EDTA content in a typical single treatment is less than 3 per cent of the total mix. This compares with more than 80 per cent of the saline and dextrose solution that makes up the majority of the cocktail. Examples of other ingredients often included are small amounts of nicotinic acid, pyridoxine hydrochloride, vitamins C, B1 (thiamin) and B5, magnesium sulphate and traces of chemicals such as heparinA substance produced by the body, or given as medication, that reduces the likelihood of the blood to clot, coagulate. and neocytamen.

Analysis of clinical trials involving around 23,000 patients over a 40-year period carried out in the early 1990s by researchers in the USA claimed a high success rate for EDTA chelation in the treatment of heart disease. But these claims have since been refuted and more recent studies have found no such benefit. [1-4]

Other forms of chelation

An alternative form of chelation for heart disease using copper in the chemical reagent tetrathiomolybdate (TTM) has also been developed in the USA. But this is essentially for use after the surgical procedure known as balloon angioplastyAn operation that uses an inflatable balloon to dilate narrowed blood vessels., a method of widening affected arteries by threading an inflatable tube into them. Scientists at Maine Medical Center Research Institute in the USA found that copper chelation stopped inflammationThe body’s response to injury. of the arteries after surgery and helped prevent arterial plaques growing back. [5]

It has also been claimed that an oral version of EDTA chelation using a form of EDTA called caysine, which was developed by a heart patient in the USA, works better and faster than conventional intravenous chelation (there are 52 varieties of EDTA, some of which are of better quality than others). However there appears to have been no independent testing of this claim to date. [6]

Safety and efficacy

The US National Institutes of Health (NIH), representing both the National Center for Complementary and Alternative Medicine and the National Heart, Lung, and Blood Institute in the USA, began a major 5-year study of EDTA chelation for CVD in 2002 that it hoped would settle the safety and efficacy argument once and for all. However, trials were suspended because of worries about safety and ethics following allegations that very rare side-effects included heart failureFailure of the heart to pump adequately., kidney damage and a drop in blood pressure and bloodA fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. cellThe basic unit of all living organisms. counts. The trials were restarted in 2009.

Called the Trial to Assess Chelation Therapy (TACT), the study is being carried out at 120 centres across the USA and Canada and involves 2,372 people aged 50 years and over who have had a heart attackThe death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction.. It claims to be the first large-scale multicentre study to find out if EDTA chelation therapy is safe and effective for people with coronaryRelating to the arteries supplying the heart itself. heart disease.

Among a variety of side-effects from chelation therapy that NIH says will be tested is a commonly felt burning sensation at the point where the chemical mix enters the body through the dripA means for the continuous injection into a vein.. Other, rarer, side-effects that will also be checked are headache, nausea, high temperature and vomiting.

The results of the study will not be known before 2014. In the meantime, NIH has repeated earlier warnings that vitamin and mineral supplements should be taken during chelation therapy because the treatment removes essential nutrients from the body.

It also cautions against having treatment administered by anyone who is not a trained health professional and states that people having chelation should continue with any heart disease treatments prescribed by a doctor.

References: 
  1. Meta-analysis (Ohio) of 19 research papers 1953-1993, Journal of Advancement in Medicine (USA), 1993.
  2. Chappell LT, Janson M. EDTA chelation therapy in the treatment of vascular disease. J Cardiovasc Nurs. 1996; 10(3): 78-86.
  3. Knudtson ML, Wyse DG, Galbraith PD et al. Chelation therapy for ischemic heart disease: a randomized controlled trial: Program to Assess Alternative Treatment Strategies to Achieve Cardiac Health (PATCH) Investigators. JAMA. 2002; 23-30; 287(4): 481-6.
  4. Dans AL, Tan FN, Villarruz-Sulit EC. Chelation therapy for atherosclerotic cardiovascular disease. Cochrane Database of Systematic Reviews 2002, Issue 4. Art. no.: CD002785. DOI: 10.1002/14651858.CD002785.
  5. Mandinov L, Mandinova A, Kyurkchiev S et al. Copper chelation represses the vascular response to injury. Proc Nat Acad of Sci USA, 2003; 100(11): 6700-6705.
  6. Angioprim: the best solution for EDTA chelation therapy.' Link