Battle lines have been drawn between those who view chelation therapy as a safe and effective alternative to bypass surgery, and the vast majority of the medical establishment that believes it to be one of the greatest-ever frauds foisted upon heart patients.

Chelation involves an intravenous drip of molecules into the bloodstream called ‘chelators’, which can remove toxic metals such as lead, mercury and aluminium from the body. The chelating agent most often used is ethylenediaminetetraacetic acid (EDTA), which can supposedly mop up the metals that, if left alone, can trigger the production of free radicals. They are also supposed to clean up the calcium deposited in the arteries, although it’s recognised that calcium is an effect, not a cause, of arterial plaque.

Although chelation practitioners pointed to the thousands of patients they said they helped, doctors nevertheless maintained that there was no scientific evidence for these claims. Things came to a head in 2003 with the release of the results of the PATCH study, which had monitored the progress of 47 heart patients, half of whom had been given EDTA chelation, and the remainder, a placebo. After six months, the chelation group’s arterial flow was no better than that in the placebo group. Chelation practitioners have since argued that the study was too small - and flawed.

The study appears to have only hardened the positions of both camps, leaving patients as puzzled as ever (J Am Coll Cardiol, 2003; 41: 420-5).