Fewer than half of Americans with stable heart disease get guideline-recommended medicines before being rushed off for an invasive heart procedure, researchers said Tuesday.

Yet the costly procedure, called percutaneous coronary intervention or PCI, offers few proven benefits over drug therapy and puts patients at risk of side effects.

“I always encourage patients to be proactive members of their own healthcare team, and they certainly should be asking doctors if they are on the right medicines,” said study researcher Dr. William B. Borden, of the Weill Cornell Medical Center in New York.

During PCI, a cardiologist guides a thin plastic tube to the heart via an artery to look for cholesterol plaques. Such buildups narrow the arteries and limit blood supply to the heart, which can cause chest pain and other symptoms during physical activity.

The doctor then inflates a balloon at the end of the plastic tube to break up the plaque, leaving behind a metal mesh tube called a stent to keep the artery open.

Studies show patients usually believe the procedure will cut their risk of heart attacks and death. But, in fact, it doesn’t work any better than drugs for people who haven’t had heart attacks before.

That became clear in 2007 after the publication of a large trial known as COURAGE that compared the PCI procedure followed by “optimal” drug therapy to treatment with the drugs alone.

On the other hand, PCI may lead to complications such as stroke, emergency bypass surgery or even death in up to one percent of patients.

In the new study, published in the Journal of the American Medical Association, Borden and his colleagues used data from more than a 1,000 U.S. hospitals to see how often patients were put on drugs before they underwent PCI.

They included more than 467,000 people with chest pain due to narrowed arteries in the heart - so-called stable coronary artery disease.

Overall, 44 percent of the patients were on guideline-recommended drugs - cholesterol-lowering statins, blood-thinning aspirin and blood pressure drugs - before they had PCI. After the procedure, the number climbed to almost two-thirds.

From the start of the study in 2005 until 2009 - two years after the COURAGE trial - those rates rose only a few percent.

“This was a 33.5-million-dollar trial, the COURAGE trial, that we found did not have much impact on practice patterns,” Borden told Reuters Health. “As we as a country invest money in comparative effectiveness research, we need to also find out how to best translate those findings into clinical practice.”

Experts say more than one million Americans undergo PCI every year, at a price that exceeds drug therapy by more than $10,000. The procedure may work better than medicine for some, but many do well on drugs alone.

Last year, Dr. William Boden, who led the COURAGE study but was not involved in the new research, told Reuters Health that doctors ought to think twice before they sign stable patients up for PCI.

“It would be like hitting the ‘pause button,’” said Boden, medical director of cardiovascular services at Kaleida Health in Buffalo, New York. “That way, the patient could confer with his/her private or referring physician, weigh the pros and cons of each therapeutic choice, or give a trial of medical therapy a good chance to work before proceeding straight-away to urgent PCI.”

But he added that the current healthcare system is not set up to favor that approach.

“There are no financial disincentives to avoiding PCI,” Boden said. “On the contrary, in a fee-for-service model, physicians are paid for doing procedures.”

Concluded Borden: “Hopefully our study will shine a light on the importance of providing medical therapy to patients before they receive stents.”

SOURCE: Journal of the American Medical Association, online May 10, 2011.