Clinical Management and Outcomes Based on Functional CAD-RADS Compared to Anatomical CAD-RADS in Patients with Stable Coronary Artery Disease.
TL;DR
Functional CAD-RADS may offer improved predictive power for moderate-term outcomes compared to anatomical CAD-RADS, suggesting potential clinical utility in guiding patient management and informing treatment algorithms for CAD, particularly in patients with intermediate stenosis.
Abstract
Purpose
While anatomical Coronary Artery Disease Reporting and Data System (CAD-RADS) is widely used for coronary CT angiography (CCTA) reporting, it has limited specificity for predicting lesion-specific ischemia. This study evaluates whether the novel functional CAD-RADS, integrating CT-derived fractional flow reserve (CT-FFR), provides superior 5-year prognostic value in patients with stable coronary artery disease (CAD).
Methods
A single-center prospective cohort study enrolled 1096 participants aged ≥18 years with CAD referred for CCTA with stenosis degrees of 25%-80%. Primary endpoints were major adverse cardiac events (MACE). The appropriateness of management decisions relative to anatomical or functional CAD-RADS recommendations was explored. Statistical analyses included Kaplan-Meier estimates, Cox proportional hazards models, measures of integrated discrimination improvement (IDI) and net reclassification improvement (NRI).
Results
After a median follow-up of 64 months, 158 MACEs occurred. Both functional and anatomical CAD-RADS categories predicted MACE (p < 0.001). Functional CAD-RADS showed a higher C-index (0.780; 95% confidence interval [CI]: 0.764, 0.796) compared to anatomical CAD-RADS (0.723; 95% CI: 0.703, 0.743) for predicting MACE (p=0.035), with improved discrimination (IDI: 0.053 [95% CI: 0.016, 0.110]; p=0.008). The proportion of inappropriate management decisions was lower for functional CAD-RADS (9.9%) than for anatomical CAD-RADS (11.0%, p<0.001). The hazard ratios for MACE when comparing dichotomous appropriate and inappropriate management decisions relative to functional CAD-RADS were 9.544 (95% CI: 5.794, 15.720; p<0.001), and 2.475 (95% CI: 1.369, 4.474); p<0.001) for anatomical CAD-RADS recommendations, corresponding to the number needed to treat of 1.912 (95% CI: 1.605, 2.364), and 5.076 (95% CI: 3.546, 10.204), respectively.
Conclusion
Functional CAD-RADS may offer improved predictive power for moderate-term outcomes compared to anatomical CAD-RADS, suggesting potential clinical utility in guiding patient management and informing treatment algorithms for CAD, particularly in patients with intermediate stenosis.