Use of Initial Noninvasive Cardiac Testing and Association with Downstream Healthcare Resource: A Retrospective Review of Resources Used Across a 12-Month Window for Probable Type I Myocardial Infarction Patients

BACKGROUND: Clinical guidelines provide clinicians with substantial discretion in the use of noninvasive cardiac testing for patients with suspected coronary artery disease. Repeat testing, frequent emergency department (ED) visits, and increases in other cardiac-related procedures can be a burden on patients and payers and can complicate treatment planning. We assessed downstream healthcare resource utilization (HCRU) for patients undergoing initial single-photon emission computed tomography (SPECT), myocardial perfusion imaging (MPI), stress echocardiography (ECHO), or exercise treadmill testing (ETT) with probable type I myocardial infarction (MI). METHODS: Electronic medical records data from 12,130 patients with probable type I MI presenting to EDs within a large healthcare system comprised of 11 adult hospitals were retrospectively analyzed. Logistic and linear regression determined the individual contribution of SPECT-MPI, ETT, and ECHO on repeat cardiovascular (CV) testing, inpatient visits, outpatient visits, and cardiac-related costs within 12 months of the index visit. RESULTS: The majority of patients received SPECT-MPI for the index-testing event (56.5%), followed by ETT (29.2%) and ECHO (14.3%). Patients who had SPECT-MPI at the index visit were less likely to have a repeat CV testing visit (odds ratio [OR] 0.77, 95% confidence interval [CI] 0.62‒0.96; p = 0.020) or an inpatient visit (OR 0.70, 95% CI 0.49‒0.98; p = 0.039) than those who underwent ETT or ECHO. ETT and ECHO were not predictive of any outcome. CONCLUSIONS: SPECT-MPI does not result in more downstream HCRU than ETT or ECHO and is associated with a lower likelihood of repeat non-invasive CV testing and inpatient visits.