ACC: 1 in 9 elective PCI procedures classified as inappropriate
To better determine the level of appropriate PCI usage in the U.S., researchers from the Mid America Heart Institute in Kansas City, Mo., used the NCDR-Cath/PCI registry to classify procedures as appropriate, inappropriate or uncertain. And while the majority of procedures were deemed appropriate, one in nine elective PCI procedures were classified as inappropriate, according to a study presented at this year’s annual American College of Cardiology (ACC) scientific sessions in New Orleans.

While appropriate use criteria (AUC) for coronary revascularization procedures were published in 2009, the appropriateness of PCI procedures in clinical practice was not defined. To better understand the variations of PCI procedural usage within the U.S., the researchers used the NCDR-Cath/PCI registry data from July 2009 to June 2010 to classify PCI procedures into the three aforementioned categories according to the AUC for coronary revascularization.

“For a long time, we have been using published guidelines for the use of coronary bypass surgery and PCI, but there is a fundamental difference between guidelines documents and appropriate use criteria,” Gregory J. Dehmer, MD, co-author of both the study and AUC criteria for revascularization, and director of the division of cardiology at Scott & White Healthcare in Temple, Texas, told Cardiovascular Business.

Guidelines are evidence-based recommendations; however, Dehmer offered that sometimes there are knowledge gaps about treatment certain situations and this may make it more difficult to know exactly how best to treat a particular patient. The AUC for coronary revascularization procedures was developed to address some of the gaps in our knowledge of how to best use revascularization procedures to deal with overuse and underuse of these procedures. Dehmer also noted som recent and well published "unfortunate cases" where stenting may have been overused and commented that application of the AUC should help address these concerns.

“Appropriate use criteria are a very important tool that allow individuals, whether they are payors or patients, to make some assessment about the use of PCI at a particular facility,” Dehmer offered.

The researchers were able to classify 354,161 of the total 434,217 PCI procedures at 912 centers. Overall, of the 354,161 procedures, 85 percent were deemed appropriate, 11.2 percent were deemed uncertain and 4.1 percent were deemed inappropriate.

“It’s important to understand what the uncertain category really means,” said Dehmer. It doesn't mean that these procedures were “wrong or right,” he said but rather it means one of two things, that there was not enough clinical information to decide whether the PCI was appropriate or inappropriate, or it identifies a “knowledge gap” where there is not enough clinical information to say with a high degree of certainty what the most appropriate treatment strategy would be in particular case.

To add to these data, researchers broke down PCI into two categories, acute—MI, STEMI or non-STEMI—or non-acute (elective) procedures. There were 254,473 procedures performed in an acute setting compared to 98,688 that were performed in a non-acute setting.

“The results for acute PCI procedures were incredibly striking,” offered Dehmer. In fact, 98.6 percent of the acute procedures were deemed appropriate and only 1 percent was classified as inappropriate.

“This was an astounding frequency of appropriate procedures,” he said. “However, because the indications for doing an acute PCI procedure are so crisply defined there is really no surprise that the frequency of appropriate procedures is so high.”

On the other hand, about half of the non-acute procedures were deemed appropriate (50.4 percent), 38 percent were classified as uncertain and 11.6 percent were classified as inappropriate.

So, why the big variation?

“When it comes to doing elective procedures there are more variables to consider and it takes more judgment on the part of the physician because each patient is somewhat unique,” said Dehmer. When deciding whether to perform these procedures in the non-acute setting, guidelines may not be as well-defined as those used in the acute setting. Dehmer offered that in the acute setting, “It is black and white whether or not the patient ought to have a PCI procedure.”

Within the non-acute cases, two-thirds of patients who underwent PCI procedures judged as “inappropriate” had minimal to no angina and 72 percent were deemed low-risk by noninvasive stress tests.

In fact, in most of these cases, patients had very few or no symptoms.  “According to our current treatment recommendations, the main reason to do an elective PCI procedure is to relieve symptoms, or address a high-risk situation, it’s not to prolong life, so that was the main reason these were classified as inappropriate,” Dehmer noted.

“If the patient is asymptomatic or has very few symptoms it’s hard to make their symptoms go away and if their stress test says they are low-risk then you have to ask yourself why is this procedure being done?”

Dehmer said that we will probably never get to a point where there are zero inappropriate procedures because there will not be enough clinical information to grade each and every procedure. When the AUC were under development it was estimated that there are over 4,000 possible clinical scenarios for PCI, “to characterize every single individual patient would have make the appropriate use criteria as thick as the New York City phonebook.

“It is inevitable that a few procedures will be judged as inappropriate because there will always be some variable to consider in an individual patient that requires physician judgement to make the final decision. The AUC provide guidance to physicians, but they are not meant to be a strict cookbook," said Dehmer.

However, the AUC will help individual facilities and interventional cardiologists identify their own procedures as appropriate, uncertain or inappropriate and understand where they are performing in comparison to the benchmarks.

“In this profession we have the privilege to regulate ourselves to make sure we are doing procedures that are in the best interest of patients in every individual patient case,” Dehmer offered.

“Before appropriate use we couldn’t measure what we’re doing, now this gives us a benchmark and we are able to work toward areas where we need improvement and then begin making those improvements.”