Placebo Effect of the Heart

November 9, 2017

After 40 years, millions of procedures, and billions of dollars, doctors are questioning whether a common procedure is doing more harm than good. How much does heart disease depend on a patient’s state of mind?

A doctor stands over you and feeds a long wire up the inside of your body, from your groin into your heart. You are conscious and comfortable, if not necessarily calm.

For nearly half century, cardiologists have been performing angioplasty, or percutaneous coronary intervention (PCI). The point is to open up arteries that have become clogged and hardened by years of life—to reverse and improve the symptoms of heart disease. Today the procedure is done around a million times each year in the U.S. alone. In the span of 45-minutes or so, the looming cardiologist watches a screen as real-time X-ray images show the wire going up to the heart, traversing vessels to reach the coronary arteries. The cardiologist then feeds a small balloon over that wire and inflates it, forcing open the blood vessels at the point of narrowing. The vessels can be held open with a metal tube that expands over the balloon, known as a stent. Immediately, the vessels look better on the X-ray images. The narrow area is wide open, and blood is flowing freely.

“When we tell a patient, look, we ‘fixed’ you, this has an immense positive effect,” said John Mandrola, a cardiac electrophysiologist in Louisville, Kentucky.

He and many others have watched as their patients tend to report less chest pain, more energy, better stamina, and “all sorts of benefits.” As the Mayo Clinic tells readers of its site, “Angioplasty is used to treat a type of heart disease known as atherosclerosis. Atherosclerosis is the slow buildup of fatty plaques in your heart’s blood vessels. Your doctor might suggest angioplasty as a treatment option when medications or lifestyle changes aren’t enough to improve your heart health, or if you have a heart attack, worsening chest pain (angina), or other symptoms.”

“Your doctor” may be wrong in doing so, though, according to a controversial study published last week that, if widely accepted, has the potential to change the course of medicine. Data in The Lancet showed that among people with severe blockage of the coronary arteries, the procedure did not improve angina—the reason for nearly 500,000 PCI procedures worldwide every year—or ability to exercise on a treadmill. Now after 40 years, millions of procedures, and billions of dollars, doctors are questioning whether the common procedure is, in most non-emergency cases, doing much less good than previously believed, if any.

Though many patients and doctors swear it works. Mandrola describes a typical case: A patient is told they should have this cardiac catheterization because of chest pain and a cardiac stress test that suggests disease. Patients come to understand from friends and the internet that if a blockage is found, the doctor will “fix it.”

“Blockages are deadly and must be fixed, goes the thinking,” Mandrola explained. “So they do the PCI, and they bring the family into the lab or show them pictures of the blockage. Everyone is happy. Doctors, nurses, patient, and family. That whole scenario creates a whirl of placebo effect. And the patient feels better.”

“I’ve been saying for many years that we don’t know if patients feel better from stents, or if they feel better because patients always feel better when we do an invasive procedure,” said Rita Redberg, a professor of medicine at the University of California, San Francisco. “That’s how the mind words.”

Knowing that this procedure’s effect is based heavily in placebo, it would seem, will diminish its effect. Reading this article may cause people to have more chest pain.

If stents to open clogged coronary arteries indeed don’t help people in non-emergency situations, this would be among the highest stakes disappointments in medicine to date, when more than anything else, people around the world die of heart disease. It usually involves blood vessels getting progressively clogged up and then totally blocked. This causes the heart muscle to die, and so the person dies.

“This is a hugely disruptive study,” said Mandrola. “The implications are huge. Billions of dollars have been spent, and many hundreds of thousands of patients have been exposed to the risks of PCI, without any documented benefit.”

Redberg went even further. “I think this has shown definitively that there was no benefit on exercise time, no benefit for angina, no benefit for functional status—it was pretty definitively negative.”

So are there any reasons—outside of an acute heart attack—to do PCI?

“I can’t think of one,” she said. “Why have a person undergo the risk of the procedure?”

Mayo Clinic makes these risks clear: The abridged version includes blood clots, heart attack (the wire can displace some of the plaque inside the wall of the artery and actually cause a heart attack), coronary-artery damage (recall that there is a wire and force-inducing balloon being inserted into the three-millimeter vessels on the surface of the heart), abnormal heart rhythms, kidney failure, and stroke. These are rare outcomes, but they become increasingly relevant as the benefits of the procedure become less clear.

The problem highlights the disconnect between how the world should be and how it is. This disease seemed so straightforward. It required no genius to suggest that the blockage of vessels could be fixed by opening up the vessels. In much the same way that a plumber removes a ball of hair and a shower is instantly new again, a cardiologist might remove years of living hard and restore the flow of blood to the heart.

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