Untangling Cardiovascular Disease, Part 4

The treatment that shall not be named

This article is dedicated to my dear brother Jeff, may he rest in peace, taken from those who loved him by a heart attack at only 59 years old. May the information I’ve spent many months researching help you, and those you love.

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This is Part 4 of a series, so in case you’re joining me now for the first time, please start at Part 1, as these chapters build on each other. I had intended for this to be the last installment in this series, but there will be a Part 5, as there’s so much to say about Untangling Cardiovascular Disease.

In Part 3, I wrote about the short, stocky, dim-witted bald man who talked my ear off at a medical conference in the 1990’s. He turned out to be an alternative medicine doc and the treatment he was speaking about was chelation, the process of removing heavy metals from the body. Although a standard treatment for heavy metal poisoning, its use for other conditions, including cardiovascular disease, has been mired in bitter controversy for decades.

Before moving on I want to make one thing explicitly clear: This is not an article endorsing or disparaging chelation for cardiovascular disease. I’m making no public recommendation regarding its use. This is part of my continued and unwavering effort to neutrally evaluate important scientific topics, even the ones which are most polarizing to the medical community.

And I came into this quite polarized myself—In the first few years of medical practice, I was 100% convinced that chelation had no role in cardiovascular disease because that’s what I was taught in medical school. And to this day, a quick online search of chelation paints its use for vascular disease as dangerous and ineffective. From WebMD:

“When metals like lead, mercury, iron, and arsenic build up in your body, they can be toxic. Chelation therapy is a treatment that uses medicine to remove these metals so they don't make you sick. Some alternative health care providers also use it to treat heart disease, autism, and Alzheimer's disease. But there's very little evidence it works for those conditions. In fact, chelation therapy can cause serious side effects -- including death -- especially if it's used in the wrong way.”

And yet I’m brought back to the short, stocky, dim-witted bald man. He relayed his experience of chelation being effective for his cardiovascular disease patients. He told me that it improved quality of life, functional status, and decreased bad cardiovascular outcomes, such has heart attack and the need for cardiac surgery. Unconvinced, bored, and a bit annoyed, I abruptly excused myself from the conversation, oblivious of my arrogance—And I didn’t give a 2nd thought to chelation, or him, again for over a decade. I wonder what he’d think if he knew that over 25 years later I still thought about that chance encounter, and how it helped shape me as a person.

TACT

Apparently mainstream medicine had been flooded with similar stories from other alternative medicine doctors, because researchers from Columbia, Harvard, NIH, and other large institutions agreed to do a prospective randomized placebo-controlled study, called TACT (Trial to Assess Chelation Therapy), to evaluate the cardiovascular outcomes of chelation in patients with a history of prior heart attack.

Chelation is a general term, describing the action of a group of chemicals which bind to heavy metals so that they can be more easily excreted. Each works differently in the body, with its own distinct risks. This article will not be exploring all types of chelation—The discussion today is limited to EDTA, which was studied in TACT.

The risks of chelation are many, and potentially serious, but given that about 100,000 people in the US are chelated each year, the safety statistics are generally good. A commonly-held opinion is that chelation can be done safely when used properly.

The type of chelation studied in TACT was IV disodium EDTA, arguably the most dangerous kind, due to its potentially fatal side effects of lowering blood calcium levels. Low blood calcium can cause potentially life-threatening cardiac rhythm disturbances.

It’s unclear to me why disodium EDTA was used instead of calcium EDTA, aka calcium disodium EDTA, as calcium EDTA doesn’t usually lower blood calcium. Although calcium EDTA can cause kidney damage when used in high dosages, a meta-analysis demonstrates that it can be helpful in humans with chronic kidney disease when used properly.

Some expected TACT to prove that chelation didn’t work for cardiovascular disease, to put the final nail in its coffin—But that didn’t work out as planned.

Black Swan

This study has been referred to as a black swan, which is a highly unexpected event, by one of its authors, Dr. Gervasio Lamas. A comprehensive video review of the science behind the study can be found here.

Dr. Lamas writes candidly about his pre-existing bias against chelation, and how he overcame it:

“I have to admit that until 1999, I had no particular interest in studying a pariah therapy called EDTA chelation -- really just not my style…I never had an interest in alternative medicine. At the Brigham, we knew it was bunk. An eccentric patient showed up on a slow clinic day and asked if he should receive chelation therapy. Obviously, I said, "no way!" But the question got me to rediscover the obvious: absence of evidence of efficacy is not the same as evidence of absence of efficacy. I also rediscovered that the epidemiologic evidence that many metals have cardiovascular toxicity at barely measurable levels is robust, particularly for lead and cadmium, metals chelated by EDTA.”

I have great personal and professional respect for Dr. Lamas because I realize how difficult it was to confront my own biases about chelation, the genesis of which stemmed from my medical training. As humans, we all have biases. I think that recognizing that fact is most of the battle. And it’s a battle that’s worth fighting—In medicine, biases are roadblocks to the advancement of science. Doctors are painfully human, biases, warts, and all.