Abstract: | BackgroundThis study aimed to investigate the diagnostic value of comprehensive on-site coronary computed tomography angiography (CCTA) using stenosis and plaque measures and subtended myocardial mass (Vsub) for fractional flow reserve (FFR) defined hemodynamically obstructive coronary artery disease (CAD). Additionally, the incremental diagnostic value of off-site CT-derived FFR (FFRCT) was assessed.MethodsProspectively enrolled patients underwent CCTA followed by invasive FFR interrogation of all major coronary arteries. Vessels with ≥30% stenosis were included for analysis. On-site CCTA assessment included qualitative and quantitative stenosis (visual grading and minimal lumen area, MLA) and plaque measures (characteristics and volumes), and Vsub. Diagnostic value of comprehensive on-site CCTA assessment was tested by comparing area under the curves (AUC). In vessels with available FFRCT, the incremental value of off-site FFRCT was tested.ResultsIn 236 vessels (132 patients), MLA, positive remodeling, non-calcified plaque volume, and Vsub were independent on-site CCTA predictors for hemodynamically obstructive CAD (p < 0.05 for all). Vsub/MLA2 outperformed all these on-site CCTA parameters (AUC = 0.85) and Vsub was incremental to all other CCTA predictors (p = 0.02). In subgroup analysis (n = 194 vessels), diagnostic performance of FFRCT and Vsub/MLA2 was similar (AUC 0.89 and 0.85 respectively, p = 0.25). Furthermore, diagnostic performance significantly albeit minimally increased when FFRCT was added to on-site CCTA assessment (ΔAUC = 0.03, p = 0.02).ConclusionsIn comprehensive on-site CCTA assessment, Vsub/MLA2 demonstrated greatest diagnostic value for hemodynamically obstructive CAD and Vsub was incremental to all evaluated CCTA indices. Additionally, adding FFRCT only minimally increased diagnostic performance, demonstrating that on-site CCTA assessment is a reasonable alternative to FFRCT. |