RATIONALE AND OBJECTIVES: PET-derived myocardial flow reserve (MFR) is a powerful prognostic indicator in coronary artery disease. We devised a new method for CS flow quantification using 320-row dynamic coronary CT angiography (CCTA) and investigated the relationship between CS flow determined via CCTA and MFR obtained via MATERIALS AND METHODS: Forty patients with significant coronary stenosis on dynamic CCTA who subsequently underwent adenosine-stress NH RESULTS: CS start time was significantly delayed in patients with MFR <
2.0 versus patients with MFR ≥ 2.0 (0.24 ± 1.20 versus -1.47 ± 1.29 sec, p = 0.0002). Multivariate logistic analysis showed that CS start time (odds ratio, 5.191
95 % confidence interval, 2.038-22.194) and CAD-RADS (odds ratio, 4.207
95 % confidence interval, 1.319-19.725) were independent associated factors with MFR <
2.0. The diagnostic performance of patients with MFR <
2.0 by receiver-operating-characteristic analysis was an area under the curve 0.841 for CS start time and 0.675 for CAD-RADS. CONCLUSION: CS flow measurement by dynamic CCTA is a new noninvasive method to estimate MFR. Delayed CS start time indicates a significant decrease in MFR, which is important information for therapeutic intervention in patients with moderate or severe coronary artery stenosis.