Abstract
AIM: Coronary computed tomography angiography (CCTA)-derived fractional flow reserve (FFR(CT)) accurately diagnoses ischemic lesions of intermediate stenosis severity. However, significant determinants of FFR(CT) have not been fully evaluated. METHODS: This was a sub-analysis of the Treatment of Alogliptin on Coronary Atherosclerosis Evaluated by Computed Tomography-Based Fractional Flow Reserve trial. Thirty-nine diabetic patients (117 vessels) with intermediate coronary artery stenosis [percent diameter stenosis (%DS) ＜70%] in whom FFR(CT) was measured were included in this study. CCTA-defined, vessel-based volumetric and morphological characteristics of plaques were examined to determine their ability to predict FFR(CT). RESULTS: Patient-based, multivariate linear regression analysis showed that hemoglobinA1c, triglycerides, and the estimated glomerular filtration rate were significant independent factors associated with FFR(CT). Vessel-based, univariate linear regression analysis showed that the total atheroma volume (r=－0.233, p=0.01) and the percentage atheroma volume (PAV) (r=－0.284, p=0.002) as well as %DS (r=－0.316, p=0.006) were significant determinants of FFR(CT). Among the plaque components, significant negative correlations were observed between FFR(CT) and low- (r=－0.248, p=0.007) or intermediate-attenuation plaque volume (r=－0.186, p=0.045), whereas calcified plaque volume was not associated with FFR(CT). In the left anterior descending coronary artery (LAD), the plaque volume of each component was associated with FFR(CT). CONCLUSIONS: Plaque volume, PAV, and %DS were significant determinants of FFR(CT). Plaque morphology, particularly in LAD, was associated with FFR(CT) in diabetic patients with intermediate coronary artery stenosis.