The prevalence and harm of unnecessary stents

A new report from the Lown Institute finds that U.S. hospitals performed more than 229,000 unnecessary stents on Medicare patients from 2019-2021, at a total cost of $2.44 billion.

While coronary stents can be lifesaving for an acute heart attack, decades of research shows that they are not beneficial for patients with stable heart disease. Yet hospitals perform hundreds of thousands of these procedures unnecessarily, exposing patients to needless risk and wasting billions.

Why do doctors continue to do procedures without evidence they benefit patients? At a panel discussion hosted by the Lown Institute, overuse experts David Brown, Thomas Power, Betty Rambur, and Vikas Saini discussed the implications of stent overuse, what causes overuse, and what we need to change. Watch the full video recording of the event below:

How prevalent is stent overuse?

The Lown Institute report found that more than one in five stents that hospitals performed from 2019-2021 for Medicare patients met criteria for overuse. Stents were defined as meeting overuse criteria for patients with a diagnosis of ischemic heart disease at least six months prior to the procedure, excluding patients with a diagnosis of unstable angina or heart attack within the past two weeks, and excluding patients who visited the emergency department over the past two weeks.

The rate of overuse varied widely among hospitals; at some hospitals, more than 40 percent of all stents were overuse, while at others, fewer than 10 percent were overuse.

The panelists found these numbers illuminating, but not shocking. In fact, Dr. Brown found the hospitals on the low end the most surprising, expecting even the low outliers to have much higher overuse rates.

“[These results are] the logical consequence of unbridled overuse of services.”

Betty Rambur, Professor of Nursing at the University of Rhode Island

What’s driving stent overuse?

Our panelists pointed out many reasons why a clinician might perform an unnecessary stent. The narrative of an artery being a “clogged pipe” that just needs to be opened is very convincing both for doctors and patients. In reality, a clogged artery is indicative of systemic heart disease that requires medication and lifestyle changes; simply opening one artery won’t prevent future cardiovascular events, said Brown.

“When a patient is shown a coronary angiogram showing right narrowing of an artery… there is an intuitive desire to make it go away.”

Dr. David L. Brown, Clinical Professor of Medicine, Keck Medicine of USC

Another reason is that guidelines are far behind the evidence, making change a slow process. Medicare’s coverage guidelines allow doctors to be paid for stents that we now know do not benefit patients — as long as Medicare will still pay for them, our health system will deliver them. Specialty guidelines also have not kept up with evidence. For example, the American Heart Association’s latest chest pain guidelines are “full of recommendations for procedural overuse…modeled on the clogged pipe paradigm of coronary disease” said Brown. “They’ve been missing in action, to say the least.”

And of course, financial incentives play a role. Our fee-for-service payment system incentivizes hospitals to do more elective procedures, and gives less to hospitals spending more time with patients or pursuing preventive measures. The $2.4 billion in waste from overused stents could be put to a much better use.

“There are harms to other patients by using healthcare dollars on low-value services, thereby depriving other patients of services that are higher value.”

Dr. Thomas Power, Senior Medical Director of Cardiology and Sleep Programs at Carelon Medical Benefits Management

Despite being the wealthiest country in the world, we have a “resource-constrained system” because not everyone can access the care they need. Imagine what the billions we spend on low-value care each year could do to change that.