Fewer angioplasties are being done as professional organizations continue to review their safety and efficacy.

Fewer Americans are getting unnecessary and potentially risky heart procedures.

Unnecessary angioplasties have decreased by 50 percent in hospitals in the United States, according to a new assessment published in the Journal of the American Medical Association (JAMA).

An angioplasty involves expanding blocked arteries with a small balloon. Once a common treatment for chest pain from blocked coronary arteries, their use has been decreasing since 2009, when the American College of Cardiology and the American Heart Association released new guidelines.

The procedure is considered a critical tool in managing coronary artery disease, but they had been performed far too often, even when risks outweighed potential benefits. About one in every four deaths in the United States is due to heart disease, according to the U.S. Centers for Disease Control and Prevention (CDC).

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Researchers at the Yale School of Medicine found the proportion of non-acute angioplasties — medically known as percutaneous coronary interventions (PCIs) — considered inappropriate decreased from 26 percent in 2010 to 13 percent in 2014. Overall, the volume of non-acute PCIs decreased 34 percent. The procedure was used to treat patients with severe angina, a common yet potentially lethal chest pain that occurs when the heart doesn’t receive enough blood.

Still, there is variation in use of PCIs by hospital.

“At better-performing hospitals, less than 6 percent of procedures were classified as inappropriate. In contrast, at worse-performing hospitals, more than 22 percent of procedures were classified as inappropriate,” said the study’s senior author Dr. Jeptha P. Curtis, an associate professor of medicine at Yale School of Medicine, in a press release.

The rates of inappropriate angioplasties appeared to drop in 2011 when a report in JAMA showed that 12 percent of all the procedures done in the U.S. were considered inappropriate. National campaigns to improve performance soon followed.

In 2011, there were more than 1.2 million angioplasties performed each year in the U.S. at a cost of $26 billion, according to the Clinical Outcomes Assessment Program.

The Yale team examined data from 2.7 million procedures at 766 hospitals between July 2009 and December 2014, and logged the data into the American College of Cardiology’s CathPCI Registry.

They say these numbers reflect improvements as the U.S. healthcare system finds ways to address unnecessary procedures and spending.

In an accompanying editorial in JAMA, Dr. Robert Harrington, professor of medicine at Stanford University’s School of Medicine, said the majority of cardiologists in the U.S. “typically respond to data, evidence, and guidelines in a positive manner of adoption and change.”

“Whether it is a medication that improves patient outcomes such as statin therapy or the evolution of a technology such as the progression from balloon angioplasty to coronary stenting, the cardiovascular community has embraced data in a mostly positive way,” Harrington wrote. “Although there are some clear exceptions and much work remains, cardiovascular medicine has largely committed to using evidence to guide practice.”

“These findings likely reflect improvements in patient selection, treatment, clinical decision-making, and documentation of the factors that determine appropriateness,” Dr. Howard Herrmann, associate editor of NEJM Journal Watch Cardiology, wrote in Journal Watch.

He did note that the Yale researchers failed to address whether the controversial guidelines had “introduced new barriers to the performance of some medically necessary procedures.”

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While angioplasties can help save lives, using them inappropriately not only creates unnecessary costs, it also puts a patient at risk of pain or even death.

Angioplasty is considered less risky than coronary bypass surgery, but there are still risks of bleeding, infection, or re-narrowing of the arteries.

An angioplasty can also cause blood clots, which in turn can cause heart attacks or strokes. These are usually treated with blood-thinning medications such as aspirin or Plavix.

Women, regardless of age, are at greater risk of complications following angioplasty.

Overall, only about 6 percent of patients experience problems, according to a study released last year in the American Heart Journal.

Only 1 percent of 1,079,751 people undergoing a PCI from 2005 to 2008 died in the hospital, the study found.

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