Abstract 20058: Comparative Effectiveness of Standard Non-invasive Cardiac Imaging in Stable Outpatients: an Analysis of Downstream Testing, Interventions, and Outcomes

Introduction: We sought to determine the comparative effectiveness of different non-invasive cardiac testing strategies on downstream testing, interventions, and outcomes in stable, privately-insured outpatients. Methods: Retrospective analysis of health insurance claims data for a national sample of privately insured patients over the years 2009-2011. Individuals who received exercise electrocardiography (ExECG), stress echocardiography (SE), myocardial perfusion scintigraphy (MPS), or coronary computed tomography angiography (CCTA) for the first time as an outpatient during the year 2010 were evaluated for cardiac catheterization, revascularization, repeat non-invasive testing, and hospitalizations for acute myocardial infarction (MI) over 360 days of follow-up. Baseline characteristics were collected in the 360 day period prior to the index test. Patients were excluded if they had an emergency department encounter for chest pain or hospitalization for MI within 3 months prior to the index test. Results: A total of 528,202 patients at an average of 52 years of age were included in the final cohort. Compared with ExECG, the reference standard, SE was associated with a slightly higher rate of revascularization but lower rate of repeat non-invasive testing (Figure). MPS and CCTA were associated with significantly higher rates of cardiac catheterization, revascularization, and repeat non-invasive testing (Figure). Hospitalizations for MI did not significantly differ across index test groups. Conclusions: ExECG and SE are associated with significantly lower rates of downstream catheterization, revascularization, and repeat non-invasive testing compared to MPS and CCTA without any difference in the rate of hospitalizations for MI. MPS and CCTA may lead to overdiagnosis and overtreatment of obstructive CAD in this patient population. ![][1] [1]: /embed/graphic-1.gif