Impact of Coronary Plaque on the Precision of Computational Fractional Flow Reserve Derived from CTA / 中山大学学报(医学科学版)

ABSTRACT

ObjectiveThe fractional flow reserve （FFR） computed from coronary computed tomographic （CT） angiograms makes it possible to noninvasively assess coronary artery disease， but the impact of plaque on FFR derived from computed tomography angiography （CTA） is still unknown. The study used invasive FFR as the reference standard to analyze the impact of plaque on coronary computed tomography angiography （CCTA）-based quantitative flow ratio （CT-QFR）. MethodsThe retrospective study included 108 patients with suspected coronary heart disease （CHD） who underwent both CCTA and FFR within 60 days. CCTA images were analyzed by the software. We obtained the CT-QFR of target vessels， perfomed the quantitative and qualitative analyses on target vascular plaques， including total plaque volume （TPV）， plaque burden， calcified plaque volume （CPV）， fibrous plaque volume （FPV）， lipid plaque volume （LPV）， and the presence or absence of high-risk plaque. ResultsAccording to the difference between CT-QFR and FFR at blood vessel level， 137 target vessels of 108 patients were divided into the overestimated group （difference＞0.03， n＝29）， reference group （-0.03≤difference≤0.03， n＝88） and underestimated group （difference＜-0.03， n＝20）. The underestimated group （14.81mm3） presented higher LPV than overestimated group （1.97mm3， P < 0.05）. There was a negative correlation between LPV and the difference （P＜0.05）. ConclusionsWhen CT-QFR is used to estimate hemodynamics of coronary artery stenosis， the presence of lipid plaque may underestimate the virtual FFR.