Abstract 10369: Safety of Anatomic versus Functional Diagnostic Testing: Insights From the PROMISE Trial (PROspective Multicenter Imaging Study for Evaluation of Chest Pain)

Abstract

Introduction: Suspected coronary artery disease (CAD) is a common indication for diagnostic testing. However, a comprehensive, randomized comparison of test safety, including radiation dose, incidental findings, and test complications, of coronary computed tomography angiography (CTA) and functional tests has not been performed. Methods: All PROMISE patients completing a diagnostic test were analyzed as tested for differences between CTA vs functional tests in A) 90 day cumulative radiation dose in milliSieverts (mSv), B) index test and cumulative dose for those whose physicians intended referral for nuclear stress before randomization, C) incidental findings (all and prespecified as potentially clinically significant) and D) index test complications. Results: Of 9470 eligible patients (mean age 61, 53% women), 4633 had CTA and 4837 had functional testing (3263 nuclear stress, 1083 stress echo and 491 exercise ECG). As a strategy comparison, CTA had lower median but higher mean cumulative radiation dose than functional testing (median: 10.3 vs 11.5 mSv, p<0.001, mean: 12.5 vs 10.6, p<0.001). In a test to test comparison in 6349 intended for nuclear stress before randomization, CTA had lower index test (mean: 10.5 vs 14.1, p<0.001) and cumulative (mean: 12.4 vs 15.2, p<0.001) dose than nuclear stress. Incidental findings were more common on CTA than functional tests (43% vs 2%, p<0.001). CTA found more potentially clinically significant incidentals (19% vs 0.7%, p<0.001), including valvular disease (echo), breast uptake (nuclear), and lung nodules, pneumonia or pulmonary embolism (CT). There were no major index test complications. Minor complications occurred in 0.8% of CTAs and 0.4% of functional tests (p<0.01). In those intended for nuclear stress, complications occurred in 0.8% of CTAs and 0.5% of nuclear stress tests (p=0.17), including hypotension (nuclear) and mild contrast reaction or extravasation (CT). No CTA and 5 functional test complications led to hospitalization. Conclusions: CTA had lower median but higher mean radiation dose compared to all functional testing, but lower dose than nuclear stress. CTA had more potentially clinically meaningful incidental findings, and despite very low overall rates, more minor complications.