February 8th, 2012

Prominent Interventionalists Attack Appropriate Use Criteria for PCI

A group of leading interventional cardiologists has launched an attack on the growing role of appropriate use criteria (AUC) for PCI in the U.S. They argue that severe flaws in current guidelines render unreliable attempts to assess the rate of appropriate procedures.

In a paper published in JACC: Cardiovascular Interventions, Steven Marso and colleagues (Paul Teirstein, Dean Kereiakes, Jeffrey Moses, John Lasala, and J Aaron Grantham) criticize a study in JAMA published last year from the National Cardiovascular Data Registry (NCDR) that found a large degree of inappropriate or uncertain PCI procedures, as well as a wide range of variability among institutions. Marso et al. write that the JAMA paper sensationalized the data by focusing attention on the low rate of appropriate indications for nonacute PCI — 50.4% — while failing to point out that the study found that 84.6% of procedures in the entire study population — acute and nonacute alike — were deemed appropriate. Furthermore, given the imprecision built into the system, they ask: What is the “acceptable threshold” of inappropriate PCI?

The authors write that the AUC panel “purposefully limited involvement of the interventional community during the development process” in order to avoid having a majority of committee members “whose livelihood is tied to the technology under study.” But the under-representation of interventionalists may have biased the results, they argue. One particular case as graded by the AUC panel was the most common reason for cases to be categorized as inappropriate: the AUC committee decided that PCI was inappropriate for a patient with 1- to 2-vessel disease, no proximal LAD involvement or prior CABG, class I or II symptoms, low-risk noninvasive findings, and on no or minimal medications. But most clinicians believe this is an uncertain but not inappropriate indication, they say.  The AUC panel may have “got this one wrong,” they write.

Marso et al. also point to the “lack of specific criteria for interpreting” stress tests in the NCDR database. In addition, they disagree with the inappropriate classification of most cases of class II angina before medical therapy has been attempted, arguing that both COURAGE and BARI 2D showed that PCI is a valid option for these patients. Finally, the authors argue that the NCDR database contains numerous inaccuracies, including misclassification of patients’ angina status or noninvasive risk assessment.

One striking feature of the controversy is that two of the authors of the JAMA paper (Paul Chan and John Spertus) and two of the authors of the JACC: Cardiovascular Interventions paper (Steven Marso and Aaron Grantham) are all at the same institution: Saint Luke’s Mid America Heart Institute in Kansas City, Missouri. Marso et al.  state that 56% of cases classified as inappropriate at their institution “were misclassified  due to incorrectly coding CCS class status, not documenting angina equivalents, or inaccurate documentation of the noninvasive risk assessment findings.”

Until the NCDR database is fixed, Marso et al. write, “it could be argued” that the authors “should refrain from approving AUC-related clinical studies until such time that assurances are both valid and reliably collected.”

Comments on this item are closed. To keep the conversation in one place, please comment here: (In)Appropriate PCI: An (In)Appropriate Critique?


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