'Inappropriate' PCI Use Is Uncommon, But Improvement Needed

Reed Miller

April 06, 2011

April 6, 2011 (New Orleans, Louisiana) — A review of over 500 000 cases presented at the American College of Cardiology (ACC) 2011 Scientific Sessions shows that overuse of PCI is uncommon but that there is still plenty of room for improvement in the number of inappropriate elective PCI procedures.

This morning, Dr Paul Chan (St Luke's Mid-America Heart Institute, Kansas City, MO) presented results of a study of over 500 000 cases in the National Cardiovascular Data Registry (NCDR) from July 2009 to June 2010 that categorized each PCI as appropriate, inappropriate, or of uncertain value based on the 2009 coronary revascularization appropriate use criteria (AUC). The AUC writing committee included representatives of the ACC, Society for Cardiovascular Angiography and Interventions (SCAI), and several other cardiology organizations, including two surgical specialty groups.

Chan reported that overall, 84.6% of the procedures in the study that could be categorized were appropriate based on the AUC, while 4.1% were inappropriate and 11.2% were in categories that the AUC deems uncertain.

Former SCAI president and member of the AUC writing committee, Dr Gregory J Dehmer (Texas A&M University College of Medicine, Temple), told heartwire that the study by Chan and colleagues "really gives us our first biopsy of what is the level of appropriateness of PCI care in all of these NCDR hospitals, which include over 900 facilities."

Dehmer proclaimed that the results are "great news, especially in today's environment," referring to the recent cases of interventionalists charged with routinely performing inappropriate PCIs. "It's very comforting news for both patients and regulators," he said.

Most of the Problems in Nonacute Procedures

Of the cases that could be categorized by the AUC, 71% were acute patients, and 98.6% of these were deemed appropriate procedures while only 1.1% were inappropriate. Chan also pointed out that there was very little variation among hospitals in their rates of appropriate and inappropriate procedures for acute patients. The acute cases included were ST-elevated MIs (21.3%), non-STEMIs with documented troponin rises (20.5%), and patients with high-risk unstable angina (29%).

However, among the 29% of the categorizable elective PCIs for nonacute patients in the study, 50.4% were categorized as appropriate, 38% were of uncertain value, and 11.6% were inappropriate based on the AUC. About 71% of the inappropriate nonacute patients were low-risk according to their ischemia study results, and two-thirds were asymptomatic to very mildly symptomatic. More detail on the study will be provided when the results are published in a peer-reviewed journal. The paper is currently under review, Chan said.

The study showed wide variation from center to center in the rate of inappropriate intervention in nonacute patients, ranging from below 10% to over 30%, and the median was 10.7%, with an interquartile range of 6% to 16.7%. Some of these cases were appropriate due to special circumstances, Chan said. "However, it is unlikely that exceptions would explain this marked variation across sites" in the rate of inappropriate procedures in nonacute patients.

Mostly Good News, But Plenty of Room to Do Better

Chan agreed that the study results show that "on the whole, the US angioplasty community is doing a decent job in ensuring that most procedures are appropriate when you look at the acute and nonacute procedures all together, but we do have some work to do in the nonacute setting." He added that "no other subspecialty has taken the lead on self-regulation and self-reflection like cardiology has, and it's a tribute to organizations like the ACC that are moving this field."

Chan and Dehmer both emphasized that while there is plenty of room for reduction of unnecessary procedures, no center should expect to have a rate of 0% inappropriate procedures. There will be cases where patient characteristics not considered in the AUC make an otherwise inappropriate procedure appropriate for a particular patient. The AUC categorizes 198 clinical scenarios based on acuity of presentation, extent of coronary disease, the extent and magnitude of ischemia, the intensity of medical therapy, and the severity of symptoms, but the AUC do not consider potentially critical factors such as age, Dehmer pointed out. "For example, what you'd do for a 45-year-old guy who can't hold down a job because of his coronary disease might be different from what you do for an 85-year-old grandmother who just sits and knits all day."

"But when you have some hospitals exceeding 17%, in the upper quartile, and others at 6%, we need to learn what the hospitals with lower rates are doing differently," Chan said.

Chan also pointed that about 19% of the PCI cases that the investigators originally looked at for inclusion in the study could not be categorized by the AUC because the case record is missing some relevant information. For example, the study had to exclude patients who had stress tests but whose ischemia risk was not recorded by the referring physician. "That's something that we can improve" by emphasizing to the NCDR sites and referring physicians the importance of collecting all of the information needed to show that a procedure is appropriate.

He also noted that the AUC will soon be updated to reflect more recent clinical trials on left main and three-vessel disease, although most of those procedures are already categorized as appropriate.

Interventionalists Must Use the Data Wisely

In the future, centers participating in the NCDR will receive quarterly reports detailing the rates of appropriate, uncertain, and inappropriate PCI procedures performed at their facility, with benchmark data on how other centers are performing. The centers will also receive a line-item list of all the cases that were classified as inappropriate for that quarter so that they can subsequently develop internal quality improvements to better understand why those procedures were performed. "Maybe there are all sorts of reasons to explain it, but we need to find out why. It causes the questions to be asked and then, hopefully, if there is a reason, those reasons can be rectified," Dehmer said.

Dehmer also pointed out that the continued collection of these data will identify "gaps in our knowledge" and which types of procedures need more study. It may also help to stimulate more discussion among interventionalists about appropriateness. A recent survey by Chan et al found widespread variability of opinion among cardiologists on the appropriateness of some PCI indications.

"Hospitals should look at their rates in relationship to other hospitals and how far above or below the median they are and then look at the list of the inappropriate cases and go back and better understand if there were extenuating circumstances that made them [actually appropriate]," Chan said. "But if there is a pattern such that the majority of those inappropriate cases didn't have exceptions, then it provides a red flag, and the interventional cardiologists should discuss how this should inform their future practice. Even hospitals with low rates of inappropriate cases can use that information to see if there is further improvement they can make.

"It will be interesting to see how hospitals and physicians work together to develop the quality-improvement effort to look at these questions," he said. "The use of the reports will dictate how useful the information we're providing to physicians will be. If the reports are just put on a shelf, they won't provide hospitals any benefit."