Abstract 12914: Multicenter Study of Diagnostic Performance of Noninvasive Coronary Angiography and Dynamic Myocardial Perfusion Imaging Using Dual Source Computed Tomography: The AMPLIFiED Study

Abstract

Introduction: Single-center studies indicated a high diagnostic accuracy of dynamic computed tomography perfusion (CTP) imaging in the diagnosis of hemodynamically significant coronary artery disease (CAD). However, no prospective multicenter study has assessed the performance of combined coronary computed tomography angiography (CTA) and dynamic CTP. Hypothesis: In this prospective multicenter study, we assessed the hypothesis that dynamic CTP can provide an incremental diagnostic value over CTA detecting hemodynamically significant CAD defined by invasive coronary angiography (ICA) with fractional flow reserve (FFR). Methods: Seven centers enrolled 165 patients with suspected or known CAD, who were clinically referred for ICA. CTA and dynamic CTP were performed using dual-source CT prior to ICA. FFR was done as part of ICA in case of 26-90% coronary diameter stenosis. Hemodynamically significant stenosis was defined as of FFR<0.8 or ≥90% stenosis on ICA. Three blinded independent core laboratories analyzed CTA, CTP and ICA. Results: The study protocol was completed in 157 participants and hemodynamically significant stenosis was detected in 112 of 442 vessels (25%) and 123 of 157 patients (78%). According to receiver operating characteristic curve analysis, CTA showed an area under the curve (AUC) of 0.81 (95% confidence interval [CI], 0.73-0.86) on the patient level and 0.80 (95% CI, 0.76-0.84) on the vessel level. Adding dynamic CTP to CTA significantly increased the AUC to 0.85 (95% CI, 0.78-0.90; p=0.027) on the patient level and to 0.84 (95% CI, 0.80-0.87; p=0.002) on the vessel level. In the subgroups of patients with 1-, 2- and 3-vessel disease by CTA, the addition of dynamic CTP to CTA significantly increased AUC from 0.80 to 0.84 (p=0.041) in 2-vessel disease and from 0.65 to 0.73 (p=0.022) in 3-vessel disease, but not in 1-vessel disease (from 0.84 to 0.87, p=0.265). Conclusion: In this first prospective multicenter study on dynamic CTP, the combination of anatomical assessment with coronary CTA and functional evaluation with dynamic CTP allowed more accurate detection of hemodynamically significant coronary artery stenosis. Improved diagnostic performance with dynamic CTP was mainly obtained when multivessel disease was suspected by CTA.