Appropriate Use Criteria (AUC) for a variety of cardiac imaging procedures were developed in response to the dramatic increase in the performance of and expenditures on cardiac imaging over the last two decades. The cumulative growth in medical diagnostic imaging of 85% (2000-2009), including a near doubling in the volume of transthoracic echocardiography (TTE), has exceeded the growth of any other physician service. This increase in utilization has raised questions from governmental and private payers about potential misuse and overuse of cardiac imaging procedures and placed cardiac diagnostic imaging in the vortex of the national debate on healthcare reform. These historical facts are indisputable and are cited in virtually every publication on the AUC.
But as this narrative continues to be repeated to justify additional reforms, many of the factual underpinnings have changed. In 2010, the most recent year for which data is available, for the first time volume of imaging services to Medicare beneficiaries, including echocardiography, DECLINED. While this may well be considered a necessary correction after a decade of unfettered growth, in truth the vast majority of this growth occurred prior to 2005. As outlined in the recently published 2012 Medicare Payment Advisory Commission’s Report to Congress, from 2005-2009 all imaging services grew at modest annual rate of 3.9%, including only 2.0% in 2009, prior to the decline of 2.5% in 2010. Cardiac imaging in general, and echocardiography in particular, has followed a similar trend. Volume of echocardiography services grew 3.7%/year from 2005-2009, including only 2.2% in 2009, before declining by 1.8% in 2010. This recent pattern of utilization hardly seems excessive in an aging population with an increasing burden of cardiovascular disease.
While all the reasons for the moderation in utilization of cardiac imaging are not clear, there are some obvious contributors. Dramatic reimbursement cuts for office-based imaging procedures and bundling of billing codes which took effect in January 2010, and implementation or threats of utilization management efforts such prior authorization processes, were key factors aimed entirely at reducing utilization and containing costs. The development and publication of the AUC has also played an important role, despite the intention of the AUC to do much more than limit utilization. The stated goal of the AUC is to provide practitioners and reimbursement agencies “a rational approach to the use of diagnostic imaging in the delivery of high quality care”. To this end, the AUC documents have raised physician awareness and provided a vehicle to define the appropriateness of current clinical practice. Unfortunately, despite wide ranging impact, the AUC are still frequently viewed merely as a means to determine if an imaging test “deserves to be reimbursed”. In this new era where utilization is flat or declining, it will be critical that we now restore the intended purpose and explore ways the AUC can guide the “optimal” use of an imaging test in the best care of our patients.
In this issue of JASE, a new study may provide a window into some of the ways application of the AUC for Echocardiography could be returned to its intended goal. Ballo and colleagues investigate the application of updated 2011 AUC for Echocardiography on inpatient TTEs performed at 5 community hospitals in and surrounding Florence, Italy. This study has a number of novel features that are worthy of discussion, not the least of which is that it is performed in a country with a healthcare system with features strikingly similar to reforms being suggested or implemented here in the United States. Additionally, this study adds to a growing literature assessing the ability of the updated 2011 AUC to encompass and stratify clinical practice, describes the impact of TTEs on clinical decision making, and represents the largest cohort to date assessing use of AUC in a community practice setting. Finally, the Ballo study is the first to rigorously assess possible underutilization of TTE, a particularly important area of study given the abrupt moderation in echocardiography utilization in recent years.
Improved Representation of Echo Practice in the 2011 AUC
The Ballo study is among a handful of new studies to evaluate the updated 2011 AUC for Echocardiography. This revision of the AUC was completed in an effort to address a number limitations identified with the initial version of the AUC for TTE published in 2007. The most important of these deficiencies was incomplete representation of echo practice, with a wide range in the prevalence of unclassifiable studies (2-35%) reported in a variety of practice settings. Ballo and colleagues report near universal representation of TTE studies in this inpatient community hospital cohort (98.8%). While inpatient TTEs are known to be represented most completely by the 2007 AUC, these results are consistent with recent studies of the 2011 AUC in a range of populations. In both inpatients and outpatients, the 2011 AUC addresses nearly all indications for echocardiography (96-99%). Further, a marked improvement in representation of echo practice compared with the 2007 AUC has been demonstrated. These findings suggest that the updated 2011 AUC for Echocardiography is a comprehensive tool that encompasses virtually the entire clinical practice of echocardiography, thus removing an important barrier to widespread implementation.
The AUC and Impact on Patient Care
Another novel feature of the Ballo study is the analysis of TTE’s impact on clinical decision making. Given the well documented dearth of randomized clinical outcome studies for any cardiac imaging modality, surrogate endpoints are useful to assess whether the AUC are really helping to stratify the true clinical appropriateness of a TTE. For example, echo abnormalities have been shown to be more common in studies deemed appropriate compared with those deemed inappropriate by the 2007 AUC. We have recently submitted data from our laboratory demonstrating that important echo abnormalities are less common on inappropriate TTEs according to the 2011 AUC than they were on inappropriate TTEs according to the 2007 AUC, suggesting that the 2011 AUC do a better job of stratifying truly appropriate clinical practice. However, while useful, echo findings remain a limited endpoint to assess appropriateness. It is clear that a normal TTE in a symptomatic patient that prompts work up for non-cardiac etiologies would meet every reasonable definition of clinical appropriateness.
A TTE’s impact on clinical management represents a better surrogate for the true appropriateness of the study than abnormal findings. In the Ballo study, impact on clinical decision making was commonly present for appropriate TTEs (86.7%), but was rare for inappropriate TTEs (14%). While large randomized outcome studies are needed to determine definitively the relationship between appropriateness and impact on patient care, the findings in this study suggest that the updated 2011 AUC go a long way towards stratifying truly appropriate clinical practice.
The AUC and “Missed Opportunities”
In perhaps the most interesting feature of the Ballo study, 259 inpatients discharged without a TTE were analyzed, and 16.2% were found to have an appropriate indication for TTE according to the 2011 AUC. This evaluation of potential underutilization of TTE suggests there may be missed opportunities to perform TTE in an effort to expedite diagnosis or improve patient care. Prior to evaluating the impact of this finding, it must be noted that AUC are not practice guidelines. Practice guidelines are intended to define best practice for a particular condition and thus suggest that an intervention should generally be performed in the best care of the patient. In the AUC, an appropriate test is “generally acceptable and is a reasonable approach” for a particular condition, clearly a much different threshold.
However, continuing to use the AUC simply to justify reimbursement of an imaging test is a missed opportunity in its own right. With echo utilization leveling or even declining, the number of patients who could most effectively and efficiently be cared for with an echocardiogram, but do not receive one, will certainly rise. Thus it is critical that clinical application of the AUC evolve from a reimbursement gateway to a widely employed guide for determining when an imaging test will advance the best care of a patient. The AUC should be used to enhance the appropriateness of echo utilization, not simply diminish it. In this context, a finding that 16% of patients discharged from the hospital had an appropriate indication for TTE suggests that at least for some an opportunity may have been missed to provide the best or and most expedited care.
The AUC in Community Practice
The Ballo study represents the largest to date assessing the application of the AUC for echocardiography in a community practice. The vast majority of studies of the AUC have been performed in academic settings, which might be expected to bias appropriateness distributions. For example, in prior studies using the 2007 AUC, a significant portion of unrepresented indications for TTE were related imaging protocols in niche programs in tertiary care settings, such as solid organ transplant or atrial fibrillation ablation programs.
There have been only a few studies addressing AUC application in community or non-academic settings. Our laboratory published a comparison of our academic practice with a high quality community cardiology practice for outpatient TTE using the 2007 AUC, and found fewer unrepresented studies in the community practice but a very similar appropriateness distribution. Rao and colleagues studied the appropriateness determinations using the 2007 AUC on outpatient TTEs in a large private practice cardiology group and found a rate of inappropriate studies similar to those reported previously in academic practices. Among both inpatient and outpatient TTE studies, Willens and colleagues found no differences in AUC determinations between an academic hospital and a Veterans Administration medical center.
The Ballo study finds near universal representation of TTE utilization by the 2011 AUC in Italian community hospitals, but reports a seemingly high rate of inappropriate studies (14.7%) in this inpatient population. There are relatively few studies of AUC application among US inpatient populations, in part because of an early finding of lower inappropriate rates (5%) in inpatients compared to outpatients (15%). This is presumably due to a “change in clinical status” among most hospitalized patients, a key determinant of appropriateness throughout all versions of the AUC. While all the reasons are not clear, potential contributors to the higher rate of inappropriate TTEs in the Ballo study may include lower illness acuity in a community hospital setting and the fact that a majority of patients were taken care of by non-cardiologists. It is also interesting to speculate on whether differences in healthcare systems between the United States and Italy may have played a role.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
