Abstract
BACKGROUND: Coronary artery disease (CAD) remains one of the leading causes of mortality worldwide. Accurate assessment of myocardial ischemia is essential for guiding clinical management. This study aimed to evaluate and compare the diagnostic efficacy of coronary computed tomography angiography (CCTA) for the visual coronary analysis (VCA) of stenosis, quantitative coronary analysis (QCA), and computed tomography-derived fractional flow reserve (CT-FFR) for predicting myocardial ischemia in patients with obstructive CAD, with positron emission tomography (PET) myocardial perfusion imaging (MPI) serving a reference standard for myocardial ischemia. METHODS: Data on suspected or confirmed obstructive CAD cases with PET-MPI and concurrent CCTA were retrospectively collected. The maximum stenosis of each vessel was determined visually and measured quantitatively, and CT-FFR was derived from CCTA. Semiquantitative parameters, including summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS), were obtained from PET-MPI and then used as the reference standard for the diagnosis of myocardial ischemia. The diagnostic efficacy of CCTA for visual analysis of coronary artery stenosis, quantitative analysis, and CT-FFR for the diagnosis of myocardial ischemia and its differences were analyzed and compared via the area under the curve (AUC). RESULTS: A total of 86 cases with a mean age of 59.5±11.54 years were included. With the semiquantitative parameters of PET serving the reference standard for myocardial ischemia and stenosis ≥50% as the positive criterion for CCTA, the diagnostic efficacy for predicting myocardial ischemia was similar (P=0.878) between CT-FFR (AUC =0.780) and QCA (AUC =0.777), with both demonstrating superior performance to that of VCA of stenosis (AUC =0.701) (all P values <0.05); however, CT-FFR, as compared to QCA, had higher diagnostic specificity (90.7% vs. 66.8%) and accuracy (80.1% vs. 68.0%) (all P values <0.05); when stenosis ≥70% was the positive criterion for CCTA, the diagnostic efficacy of myocardial ischemia predicted by VCA (AUC =0.722), QCA (AUC =0.777), and CT-FFR (AUC =0.780) were all similar (all P values >0.05); however, the specificity of CT-FFR (90.7%) and QCA (91.7%) was higher than that of VCA (83.8%) (all P values <0.05). The specificity of CT-FFR in predicting myocardial ischemia was higher for intermediate stenotic coronary lesions. CONCLUSIONS: The diagnostic efficacy of CT-FFR and quantitative analysis of coronary artery stenosis for predicting myocardial ischemia was similar and higher than that of visual analysis; however, the diagnostic specificity and accuracy of the former were higher. As the degree of stenosis increased, the diagnostic efficacy of visual analysis, quantitative analysis, and CT-FFR in predicting myocardial ischemia increased. However, CT-FFR had the highest diagnostic specificity and accuracy in predicting myocardial ischemia.