The value and appropriateness of positron emission tomography: An evolving tale

The extraordinary advances in medical care during the past several decades have impacted both the quality and longevity of an individual’s life. However, impressions of modern health care have been adversely impacted by runaway expenses and the high cost of care delivery. Medical imaging, including nuclear cardiology, has demonstrated excellent value with regards to diagnosis and risk stratification, but has limited date to support its impact on patient outcome, thereby becoming the focus of public and payer attention due to concerns of overuse. This has lead to multiple initiatives to limit test performance and reduce overall spending, including pre-authorization and test substitution. As a response to fiscal pressures and with a goal of optimizing test/patient selection, appropriate use criteria (AUC) have been developed by several organizations, including the American College of Cardiology (ACC) and American Society of Nuclear Cardiology (AS]NC). Unfortunately, adoption of these AUC by private and federal health plans has been more limited than desired; many private insurers continue to use radiology benefits managers with their proprietary algorithms for test selection, often lacking consistency with medical literature and expert opinion. However, the AUC were specifically designed to serve as guidance documents for clinicians and others with regards to a variety of cardiac tests and procedures. Positron emission tomography (PET) MPI has been shown to provide improved image quality, superior interpretative confidence, and higher diagnostic accuracy than SPECT and has been considered by many to be a ‘‘gold standard’’ of non-invasive testing. In addition to its value as a diagnostic study, the independent and incremental value of myocardial perfusion PET has also been demonstrated in multiple studies, including a multicenter registry involving more than 7,000 patients. PET possesses a greater discriminatory power than other non-invasive modalities with regards to cardiac events. Furthermore, rubidium-82 perfusion PET is associated with a lower radiation burden and more rapid test performance, making this procedure an attractive test for the evaluation of known or suspect ischemic heart disease. However, the costs associated with this procedure are high, as is the level of reimbursement, which although justifiable based on procedural costs, places additional strain on an already financially overburden health system. The AUC for radionuclide imaging that were initially published in 2005 were revised and expanded in 2009 as a result of technologic advances in nuclear cardiology, feedback from ASNC and individual providers, and improvements in the development of AUC. All of the indications for radionuclide imaging (RNI) are intended for application for both SPECT and PET, unless specifically identified as being germane only to SPECT. The only stipulation regarding the AUC indications impacting PET is that exercise testing is the preferred stress modality for RNI. As exercise PET myocardial perfusion imaging is currently not an option in most centers, this preference is not applicable to PET, although the development of new PET perfusion agents, such as F-18 flurpiridaz, will make exercise testing an option in the future. Notably, there are no ‘‘pure’’ PET AUC, largely due in part to the similar applications of Reprint requests: Robert C. Hendel, MD, 1120 NW 14th Street, CRB Suite 1123, Miami, FL 33136; rhendel@med.miami.edu J Nucl Cardiol 2015;22:16–21. 1071-3581/$34.00 Copyright 2014 American Society of Nuclear Cardiology.