Quantitative Coronary Angiography for Assessment of Non-Obstructive Coronary Artery Disease: Comparison to Fractional Flow Reserve

Abstract

Objective: To assess intermediate coronary artery lesions by 2D and 3D Quantitative Coronary Angiography (QCA) and compare the results with standard fractional flow reserve (FFR). Background: FFR is the standard for assessment of physiological significance of an intermediate coronary stenosis, but it expensive, sometimes it is unavailable, or limited use by contraindications to adenosine, QCA especially three-dimensional (3D-QCA) can be used as another method to help in assessment of the intermediate coronary lesions. Patients and methods: Thirty two vessels in 30 patients with intermediate coronary lesions were scheduled for FFR, 2D and 3D QCA measurement and the results of QCA were compared and correlated to the obtained from FFR. Results: The studied group included 32 vessels, 24 diabetic patients (75%). 18 hypertensive (56.3%). 20 smokers (62.5%). Mean FFR value was 0.80 ± 0.13. FFR? 0.80 was observed in 18 lesions (56.25%). Lesions severity obtained by 3D-QCA was better correlated to FFR than 2D-QCA. Both 3D area stenosis percent and 3D diameter stenosis percent have comparable correlation in term of accuracy but with better sensitivity for the percent diameter stenosis. 2D-QCA measurements were less correlated to FFR. Conclusion: 3D QCA is better than 2D QCA in assessment of intermediate coronary lesions and it is better correlated with FFR so it may be used in assessment of intermediate coronary lesions, when FFR is unavailable or contraindicated.