A meta-analysis comparing the diagnostic performance of computed tomography-derived fractional flow reserve and coronary computed tomography angiography at different levels of coronary artery calcium score

Objectives The impact of coronary calcification on the diagnostic accuracy of computed tomography-derived fractional flow reserve (CT-FFR) and coronary computed tomography angiography (CCTA) remains a crucial consideration. This meta-analysis aims to compare the diagnostic performance of CT-FFR and CCTA at different levels of coronary artery calcium score (CACS). Methods and results We searched PubMed, Embase, and the Cochrane Library for relevant articles on CCTA, CT-FFR, and invasive fractional flow reserve (FFR). Ten studies were included to evaluate the diagnostic performance of CT-FFR and CCTA at the per-patient and per-vessel levels in four CACS groups. Invasive FFR was used as the reference standard. Except for the CACS ≥ 400 group, the AUC of CT-FFR was higher than those of CCTA in other subgroups of CACS (in CACS < 100 (per-patient, 0.9 (95% CI 0.87–0.92) vs. 0.32 (95% CI 0.28–0.36); per-vessel, 0.92 (95% CI 0.89–0.94) vs. 0.66 (95% CI 0.62–0.7); both p < 0.001), CACS ≥ 100 (per-patient, 0.86 (95% CI 0.82–0.88) vs. 0.44 (95% CI 0.4–0.48); per-vessel, 0.88 (95% CI 0.85–0.9) vs. 0.51 (95% CI 0.46–0.55); both p < 0.001), and CACS < 400 (per-patient, 0.9 (95% CI 0.87–0.93) vs. 0.74 (95% CI 0.7–0.78), p < 0.001; per-vessel, 0.8 (95% CI 0.76–0.83) vs. 0.74 (95% CI 0.7–0.78); p = 0.02)). Conclusions CT-FFR demonstrates superior diagnostic performance in low CACS groups (CACS < 400) than CCTA in detecting hemodynamic stenoses in patients with coronary artery disease (CAD). Clinical relevance statement Computed tomography-derived fractional flow reserve might be utilized to determine the necessity of invasive coronary angiography in coronary artery disease patients with coronary artery calcium score < 400. Key Points • There is a lack of meta-analysis comparing the diagnostic performance of computed tomography-derived fractional flow reserve and coronary computed tomography angiography at different levels of calcification. • Computed tomography-derived fractional flow reserve only has a better diagnostic performance than coronary computed tomography angiography with low amounts of coronary calcium. • For the low coronary artery calcium score group, computed tomography-derived fractional flow reserve might be a good non-invasive method to detect hemodynamic stenoses in coronary artery disease patients.