Observational Study on the Value of CCTA and CT-FFR in Assessing Coronary Lesion-Specific Ischemia

This observational study aimed to evaluate the diagnostic value of coronary computed tomography angiography (CCTA) and CT-derived fractional flow reserve (CT-FFR) in assessing lesion-specific ischemia. A total of 116 patients with suspected coronary artery disease (CAD) admitted between June 2023 and February 2025 underwent CCTA and CT-FFR, with invasive coronary angiography (ICA) combined with FFR as the reference standard. A total of 348 coronary segments were analyzed, and ICA-FFR confirmed 82 ischemic lesions (23.56%). The diagnostic performance of CCTA showed a sensitivity of 75.61% (62/82), specificity of 81.36% (214/266), and accuracy of 80.46% (276/343), while CT-FFR demonstrated a sensitivity of 84.15% (69/82), specificity of 89.08% (237/266), and accuracy of 87.76% (306/349). When CCTA stenosis ≥50% was combined with CT-FFR ≤0.80, diagnostic performance improved significantly, achieving a sensitivity of 89.02% (73/82), specificity of 92.48% (246/266), and accuracy of 91.40% (319/349) (all P<0.05 compared with standalone methods). Stratified analysis revealed that CT-FFR outperformed CCTA in identifying ischemia in the left anterior descending artery (AUC=0.912 vs. 0.825) and right coronary artery (AUC=0.887 vs. 0.813, P<0.05), while both methods showed comparable efficacy in left main and circumflex lesions. These findings suggest that combining CCTA with CT-FFR significantly enhances the diagnostic accuracy for lesion-specific ischemia, particularly in the left anterior descending and right coronary arteries, providing a noninvasive and efficient tool for individualized management of CAD.