Can chelation therapy help cure heart disease?
A new study shows promise for the alternative treatment, but questions remain.
Wed, Nov 07 2012 at 3:11 PM
Some alternative treatments may seem farfetched to the uninitiated, but the logic behind chelation therapy is straightforward enough. The treatment removes metals from the bloodstream, most often via an injection of ethylene diamine tetraacetic acid (EDTA). EDTA is a chemical that binds heavy metals — including iron, lead, mercury, cadmium and zinc — and flushes them from the system.
Chelation therapy using EDTA has been approved by the U.S. Food and Drug Administration (FDA) as a treatment for lead poisoning for more than 40 years — and it's even being used to save endangered California condors.
But it also used in alternative applications, such as in treatment for heart disease, cancer and other conditions. In fact, every year, more than 100,000 Americans with heart disease undergo chelation therapy. Because the process can also reduce calcium in the bloodstream, some experts believe chelation therapy can help unclog arteries blocked with mineral deposits, as in atherosclerosis or hardening of the arteries. Practitioners claim that it provides an effective and less costly alternative to coronary bypass surgery, angioplasty and other practices used to reopen arteries.
That said, it has become a controversial topic, with supporters and naysayers on both sides of the issue.
To investigate the efficacy of this off-label procedure, the National Institutes of Health sponsored a $30 million study on the topic. To the surprise of many cardiologists, chelation therapy proved beneficial to people with heart disease, reducing the rate of death and cardiovascular problems in the clinical trial, according to the New York Times.
“There may be a biological effect and that biological effect should be taken seriously,” and “pursued with additional research,” said Dr. Gervasio A. Lamas of Mount Sinai Medical Center in Miami, the lead investigator.
The study, which hit road bumps along the way, ended up with 1,708 patients who had suffered heart attacks, in the United States and Canada. Half of the patients received a series of chelation therapies with EDTA, the other half received placebo infusions.
Following up after 55 months, 26 percent of those who received chelation therapy had died or suffered a heart-related condition, while 30 percent of those who received a placebo suffered the same. The difference is small, but impossible to ignore.
A number of causes for the results have been suggested by various doctors, and many physicians remain highly skeptical. Some have said that since the placebo contained sugar, it could have affected diabetic participants, while other have noted that the legitimate infusion contained vitamin C and heparin which could have been the beneficial factor.
Dr. Elliott Antman, a cardiologist at Brigham and Women’s Hospital in Boston representing the heart association, applauded the National Institutes of Health for sponsoring the study, but also voiced caution. “Intriguing as these results are, they are unexpected and should not be interpreted as an indication to adopt chelation therapy into clinical practice,” said Antman.
"A definitive answer on chelation therapy will take much additional research," Gervasio Lamas, chief of the Columbia University division of cardiology at Mount Sinai Medical Center in Miami Beach, Fla., said in a statement. "The most exciting part of this study is that there may be an unexpected signal of benefit. We need to understand whether the signal is true, or whether it occurred by chance."
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