Researchers at Imperial College London conducted a study on 200 patients who had one severely blocked artery to the heart. The blockage was severe enough to cause chest pain that limited the person’s exercise capacity.
For six weeks, the research team gave the participants statins, aspirin and blood pressure medication, and then each patient underwent a routine procedure to insert a stent into the affected arteries.
However, half of the group was, in fact, subjected to a sham procedure, where unknown to them, the tube was withdrawn and no stent was put in place.
Some six weeks later, all participants had an exercise test. To general surprise, there was no difference in the exercise tolerance between the stent and non-stent groups. For some, this is evidence of a placebo effect, in which the suggestive power of having a procedure performed is enough to bring about improvement