THE CMG VOICE

Is Medicine Based On Science? The Example of Cardiac Stenting

Over the centuries, medicine has evolved from a “black art” to one that is based on provable scientific principles. Or at least that is the assumption. An essay in The Atlantic magazine questions how far medicine has actually advanced (“When Evidence Say No, But Doctors Say Yes”). A key example in the article is the practice of stenting cardiac vessels to prevent heart attacks.

As the article points out, interventional cardiologists participate in a major industry focused on opening up a blocked cardiac artery without surgery. This is done by inserting a thin device up through the vessel to the narrowed area and stretching it open. Sometimes the area is then kept open by placing a stent inside the vessel. It all seems intuitive to anyone who thinks of the body as, in part, a vascular plumbing system. If the pipe is narrowed, open it up, and then prop it open.

Studies have shown, however, that few patients who are otherwise stable benefit from this procedure. Putting a piece of metal in an artery carries the risk of major complications, even death. Despite this knowledge and the evidence upon which it is based, invasive cardiologists continue to make this a mainstay of their medical practices. Apart from the obvious fact that this makes a lot of money for such cardiologists, a major reason may be social and cultural, rather than scientific.

“Evidence-based medicine” has become a slogan for the “new” scientific medicine. Yet there is a dearth of solid proof of benefit for many of the medical practices that make up much of what a doctor does. The remedies are often a result of habit and custom. Other doctors do them, and they are talked about at medical meetings, so this must be what should be done.

But evidence-based medicine only works for things for which we have solid evidence. A review of the article in The Atlantic contained the following: “But for those things for which we only have intuition and sometimes guesswork it is often best to remember the famous formulation of Loeb’s laws. Many times it is best to go by this dictum when tempted for forge ahead into the mist: ‘Don’t just do something, stand there.’”