Commonly used to treat toxic conditions such as lead poisoning, chelation (kee-LAY-shun) therapy is an experimental treatment for certain progressive heart diseases. These heart diseases include the hardening and narrowing of the arteries (atherosclerosis), which may occur in the coronary arteries located on the surface of the heart coronary artery disease and is the leading cause of heart attacks. 

Chelation therapy involves the use of chelating agents such as a man-made amino acid called ethylenediamine tetraacetic acid (EDTA). These agents envelop poisonous materials and chemical toxins (e.g. mercury, lead) and transport them out of the body via the urine. Originally, chelation was used to fight nerve gas damage after World War I. In 1950s and 1960s, scientists theorized chelating agents might be able to remove calcium-based plaque in arteries. Once the plaque was removed by EDTA, the arteries would once again be clear and free-flowing. Some researchers have considered using chelation to prevent the initial build-up of plaque as well.

Medical opinion on chelation therapy has been mixed and often heated. Scientific organizations purport that medical testing on chelation and other alternative treatments is welcomed, but there is no definitive medical evidence to justify the widespread use of chelation therapy. The same holds true for the use of chelation therapy as a treatment for most other non-heart conditions, such as breast cancer and Alzheimer’s disease.

There have been patients and treatment providers who say that chelation therapy has improved or even cured conditions, but these claims have not been supported by well-controlled clinical research. It is important to note that the perceived benefits may also have been due to the conventional treatments that were done in conjunction with chelation therapy, such as:

In 2003, the National Institutes of Health launched the first large-scale clinical study to determine if EDTA chelation therapy is safe and effective in the treatment of coronary artery disease. The study, called the Trial to Assess Chelation Therapy (TACT), will include 1,950 patients 50 years and older who have experienced a heart attack. The study will compare chelation therapy to placebo to determine the overall effectiveness of chelation therapy in reducing death, heart attack, stroke, or hospitalization for angina or congestive heart failure. During the study, patients will be given the high doses of vitamins that are frequently recommended in conjunction with chelation by alternative physicians.

TACT is being conducted in more than 100 medical centers across the United States. The participants will receive 40 infusions of chelation therapy over the course of the study. Researchers hope to gain valuable insight into the effectiveness of chelation therapy in treating heart disease.