Impact of coronary lesion geometry on fractional flow reserve data from interventional cardiology research in-cooperation society-fractional flow reserve and intravascular ultrasound registry

BACKGROUND: The impact of various coronary lesion geometries on fractional flow reserve (FFR) is poorly understood. METHODS AND RESULTS: A total of 1552 coronary lesions in 1236 patients from a prospective Interventional Cardiology Research Incooperation Society Fractional Flow Reserve and Intravascular Ultrasound registry were assessed using quantitative coronary angiography, intravascular ultrasound, and FFR. Computational fluid dynamics simulation was performed for theoretical validation. Patients with complex geometries, such as longitudinal eccentricity, cross-sectional eccentricity, and surface roughness, showed significantly lower FFR values. In multivariable analysis, distal longitudinal eccentricity (adjusted odds ratio, 1.55; 95% confidence interval, 1.04–2.87; P=0.031), cross-sectional eccentricity (adjusted odds ratio, 1.65; 95% confidence interval, 1.27–2.14; P<0.001), and surface roughness (adjusted odds ratio, 1.55; 95% confidence interval, 1.04–2.32; P=0.033), as well as male sex, left anterior descending artery territory, proximal location, high degree of diameter stenosis, long lesion, and high plaque burden, were identified as independent predictors for significantly low FFR values (≤0.80). Computational simulation supported the impact of lesion geometry on FFR. CONCLUSIONS: The complex coronary lesion geometries were independently associated with reduced FFR values. The visual–functional mismatch between coronary angiography and FFR could be partly attributable to local geometric factors.