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Angioplasty and stents for non-emergency coronary artery disease is one of the most common invasive procedures performed in the United States. Though it appeared to offer immediate relief of angina chest pain in stable patients with coronary artery disease, it didn’t actually translate into a lower risk of heart attack or death. This is because the atherosclerotic plaques that narrow blood flow tend not to be the ones that burst and kill you. But hey, symptom control is important—that’s much of what we do in medicine. But cardiology has a bad track record when it comes to performing procedures that don’t actually end up helping at all.
Case in point: internal mammary artery ligation. Though it didn’t make much anatomical sense, why tying off arteries to the chest wall and breast would somehow improve coronary artery circulation, it worked like a charm. Immediate improvement in 95 percent of hundreds of patients. Could it have been just some elaborate placebo effect, and they were cutting into people for nothing? There’s only one way to find out. You cut into people for nothing.
They randomized people to get the actual surgery or a fake surgery where they cut you open and get to the last step, but don’t actually tie off those arteries. And … the patients who underwent the fake surgery experienced the same relief. Check out the testimonials. “[I]mmediately, I felt better.” “ …95 percent better.” “No chest trouble even with exercise.” “ … I’m cured!” And these are all people who got the sham surgery. So, it was just an extravagant placebo effect. Think about it. Some frightened, poorly-informed man with angina chest pain, winding himself tighter and tighter, sensitizing himself to every twinge of chest discomfort, who then comes into the environment of a great medical center and a powerful, positive, paternalistic personality and hears how great it’s going to be, goes through the whole operation and leaves a new man with his trademark scar.
One sham patient was actually cured though. “The patient is optimistic and says he feels much better.” Office note the next day: Patient dropped dead. So, no more chest pain!
This has happened over and over. I’ve got an idea! How about we burn holes in the heart muscle with lasers to create channels for blood flow. Worked great, until it was proven that it doesn’t work at all. Cutting the nerves to your kidneys was heralded as a cure for hard-to-treat high blood pressure until sham surgery proved the procedure itself was a sham. The necessity for placebo-controlled trials has been rediscovered several times in cardiology, typically to considerable surprise. Before they are debunked, often the therapy is thought to be so beneficial that a placebo-controlled trial is deemed unnecessary and perhaps even unethical. That was the case with stents.
Hundreds of thousands of angioplasties and stents are done every year, yet placebo-controlled trials had never been done. Why? Because cardiologists were so unquestionably sure it worked that it would be unethical to perform a fake procedure to prove something we already know is true. When patients are aware that they have had a stent, they have a clear reduction in angina and improved quality of life. But what if they weren’t aware? Would it still work?
Enter the ORBITA trial. After all, anti-angina medication is only taken seriously if there is blinded evidence of symptom relief against a placebo pill; so, why not pit stents against a placebo procedure. In both groups, doctors threaded a catheter through the groin or wrist of the patient, and with X-ray guidance, went up to the blocked artery, and then either inserted a stent or just pulled the catheter back out.
They had problems even getting the study funded. They were told we already know the answer to this question—of course, stents work—and that’s even what the researchers themselves thought. They were interventional cardiologists themselves. They just wanted to prove it. Boy, were they surprised. Even in patients with severe coronary artery narrowing, angioplasty and stents did not increase exercise time more than the fake procedure.
“Unbelievable” read the New York Times headline, remarking that the results “stunned leading cardiologists by countering decades of clinical experience.” In response to the blowback, the researchers wrote that they sympathize with everyone’s shock and disbelief. Yes, we could have tried to spin it somehow, but they had a duty to preserve scientific integrity.
While some commended them for challenging the existing dogma around a procedure that has become so routine, ingrained, and profitable, others questioned their ethics. After all, four patients in the placebo group had complications from the guide wire insertion and required emergency measures to seal the tear they made in the artery. There were also three major bleeding events in the placebo group; so, they suffered risks without even a chance of benefit. But “[f]ar from demonstrating the risks of sham-controlled trials, this demonstrates exactly what patients are being subjected to on a routine basis” for nothing.
Those few complications in the trial are dwarfed by the thousands that have been killed or maimed by the procedure over the years. You want unethical? How about the fact that an invasive procedure has been performed on millions of people before it was ever actually put to the test? Maybe we should consider the absence, not the presence, of sham control trials to be the greater injustice.
When a former FDA commissioner was asked at the American Heart Association meeting whether sham controls should be required for the approval of all devices, he replied, “Do you want to get the truth or not?”
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