Several theories have been proposed for how this treatment may work. One theory suggests that EDTA chelation might work by directly removing calcium found in fatty plaques that block the arteries, causing the plaque to decrease in volume. EDTA chelation therapy may work by reducing the damaging effects of oxygen ions and reactive transition metals (oxidative stress) on the walls of the blood vessels. Reducing oxidative stress could reduce inflammation in the arteries and improve blood vessel function. This is why EDTA is used to prevent the spoiling of food. It blocks oxidative reactions.
Although the vast majority of the published research is on disodium EDTA it has been removed from the market though it is still available through compounding pharmacies. This type chelates metals as well as calcium and if infused too quickly will cause hypocalcemia.
Calcium EDTA (Calcium Disodium Versenate) is safer because it does not lower serum calcium. The pharmacologic effects of edetate calcium disodium are due to the formation of chelates with divalent and trivalent metals. A stable chelate will form with any metal that has the ability to displace calcium from the molecule, a feature shared by lead, zinc, cadmium, manganese, iron and mercury. Both types of EDTA chelate transition metals.
The ability of EDTA to neutralize oxidative reactions caused by transition metals (Lamb, Mitchinson, & Leake, 1995; Stadler, Lindner, & Davies, 2004) has many beneficial anti aging effects on the body. Transition metals are those in the middle of the periodic table. Transition metals/minerals can form negatively charged complexes that are reactive. Most toxic metals (minerals) are transition metals as well as the nutritionally essential metals iron and copper. I have noticed EDTA infusions are most effective for slowing atherosclerosis when elevated levels of reactive metals are present.
LDL oxidation can only take place in the presence of transition metal ions, such as iron and copper and human plaque biopsies contain significant amounts of reactive copper and iron (Lamb, et al., 1995; Stadler, et al., 2004) whereas the blood usually does not contain these highly reactive species (Lamb, et al., 1995).
Giving more credibility to the notion that chelation is a valid treatment is published data indicating that heavy metals, particularly mercury, may contribute to atherosclerosis (Landmark & Aursnes, 2004). The negative cardiovascular effects of mercury stem from its ability to induce oxidative stress, inflammation, thrombosis, vascular smooth muscle dysfunction, endothelial dysfunction, dyslipidemia, immune dysfunction, and mitochondrial dysfunction (Houston, 2007).
Lead is very bad for the cardiovascular system as well. The main sources of lead exposure are lead-based paint, leaded gasoline, lead-soldered plumbing fixtures, pipes, and canned foods, contaminated alcoholic beverages, lead-glazed kitchen/dining utensils, and mining and industrial contamination as well as occupational exposure.Since the banning of lead-based gasoline, paint, and solder,as well as passage and enforcement of environmental regulations, exposure to lead in the U.S. has declined. Ground contamination continues to be a current source of lead exposure in the industrial societies.Heavy exposure also continues in countries where environmental regulations are lax or poorly enforced (such as India and China) (Vaziri, 2008). Keep in mind the U.S. had no regulations either roughly prior to 1960.
Lead can be absorbed via the respiratory and gastrointestinal tracts and even through the skin. Over 95% of the total body lead content resides in the bone,where it can persist for decades. As we age gradual release of lead from the bone serves as a source of toxicity long after initial exposure. Conditions such as osteoporosis accelerate the release of lead from bone. Measurement of blood lead concentration primarily reflects recent/current lead exposure and does not reveal past exposure. Measurement of urinary lead excretion after EDTA provocation provides the best estimation of total body lead burden (Vaziri, 2008).
The negative effects of lead on the cardiovascular system are really quite impressive. Chronic lead exposure causes high blood pressure, thrombosis and cardiovascular disease by (Vaziri, 2008):
promoting oxidative stress
limiting nitric oxide availability
impairing nitric oxide signaling
augmenting adrenergic activity
increasing endothelin production
altering the renin-angiotensin system
raising vasoconstrictor prostaglandins
lowering vasodilator prostaglandins
disturbing vascular smooth muscle Ca2+ signaling
diminishing endothelium-dependent vasorelaxation
causing endothelial injury and limiting endothelial and blood vessel repair
reduce endothelial cell growth
reducing tissue plasminogen activator and raising plasminogen activatorinhibitor-1 production
The fact that heavy metals cause oxidative stress and cardiovascular disease is undisputed in the literature (Valko, Morris, & Cronin, 2005; Wolf & Baynes, 2007). Critics of chelation conveniently fail to mention or look at this data. Because of the connection between heavy metals in atherosclerosis I will often screen patients for toxic metal overload and only recommend chelation for the treatment of heavy metal toxicity. Anyone who has high blood pressure and atherosclerosis should be screened for toxic metals with a urinary provocation test. In my clinic I use DMPS and EDTA.
The side benefit is less oxidative stress and better endothelial function. Since EDTA is also an anticoagulant it may work by preventing platelets from sticking together which could prevent the formation of blood clots on the walls of blood vessels. Often chelation treatments contain heparin which is anti-inflammatory and anti-coagulant.
Additionally, intravenous treatments often include high doses of magnesium and B vitamins which have their own beneficial effects. Magnesium, in particular, is an effective treatment for high blood pressure, coronary spasm and congestive heart failure. Magnesium reduces; inflammation, endothelial dysfunction, oxidative stress and platelet clumping. Magnesium also acts as a mild calcium blocker and as a vasodilator. Chelation therapy may actually work to prevent heart attacks thanks to the sum of all the biochemical and physiologic effects that is has.
Intravenous EDTA chelation may be effective in slowing atherosclerosis because it reduces oxidative stress, is anticoagulant, lowers serum calcium (depending on type used), promotes endothelial health and lowers blood pressure. A unified theory proposes that it is the synergy of all the physiologic effects that provide benefit. The net effect of undergoing chelation therapy may be a reversal of many age-related changes. Because toxic transition metals accelerate aging through damage to DNA and oxidative stress chelation treatment may play a larger role in medicine than we had once believed.