Evaluation of the American College of Cardiology Foundation/American Society of Nuclear Cardiology appropriateness criteria for SPECT myocardial perfusion imaging

Background. The American College of Cardiology Foundation/American Society of Nuclear Cardiology appropriateness criteria (AC) were created to guide responsible use of single photon emission computed tomography (SPECT). Clinical applicability of the AC has not been evaluated. Methods and Results. Indications for testing were determined in 1209 patients and categorized as having appropriate, uncertain, or inappropriate indications; the specialty of the ordering physician was noted. There were 940 (80%) appropriate, 154 (13%) inappropriate, and 79 (7%) uncertain tests; 36 tests were labeled "no category," as these were ordered for indications not clearly addressed in the AC. Inappropriate studies had more normal and lower summed stress scores, although there remained a high proportion of abnormal SPECT studies in this group (26% of women and 50% of men). Women had lower summed stress scores and more normal tests in the appropriate and inappropriate groups. Studies ordered by anesthesiologists for preoperative evaluation were more likely to be deemed inappropriate than other specialty groups. Conclusion. In evaluating the AC in a single-center academic setting, the majority of studies are appropriate, but a large proportion of ordered SPECT studies were categorized as uncertain, inappropriate, or no category. Although the inappropriate studies showed less ischemia than other groups, especially in women, a substantial portion of these studies (32%) were abnormal.