Inappropriate utilization of SPECT myocardial perfusion imaging on the USA-Mexico border

Background. The American College of Cardiology/American Society of Nuclear Cardiology published revised appropriate use criteria (AUC) for SPECT MPI in 2009. We assessed adherence to these guidelines and factors associated with inappropriate utilization at the University Medical Center. Methods. The AUC was applied retrospectively to 420 SPECT MPI studies. Two-sample t test, Fisher's exact test, and multivariable logistic regression models were used for analysis. Results. There were 322 appropriate (86%) and 54 (14%) inappropriate studies. The odds of having an inappropriate test increased with younger age (P < .001) and female gender (P < .001). Subjects with diabetes (P = .007) and chest pain (P < .001) were less likely to have an inappropriate test. Academic outpatients were three times more likely to have an inappropriate study (P = .123), while community PCPs were 5.6 times (P = .011) and community cardiologists eight times more likely to order inappropriate tests (P = .031). Conclusions. Inappropriate SPECT MPI in low risk younger women is an important issue on the USA-Mexico border. Initiatives to reduce inappropriate SPECT MPI should focus on a few indications and evaluation of cardiovascular symptoms in younger age women in outpatient/community practices.