Abstract 10976: Diagnostic Ability of Contrast Media Induced Fractional Flow Reserve to Assess Functional Significance of Entire Coronary Artery Stenosis

Abstract

Introduction: Although fractional flow reserve (FFR) is helpful to evaluate functional lesion severity, the need of adenosine limits the widespread adoption of FFR. Hypothesis: We hypothesized that contrast media induced FFR (cFFR) with submaximal hyperemic condition could assess functional lesion severity of coronary artery stenos. The aim of this study was to evaluate the diagnostic ability of cFFR compared to FFR in entire range of coronary artery stenosis. Methods: A total of 96 patients with 123 lesions were prospectively enrolled in this study. At first, we measured resting Pd/Pa ratio before inducing hyperemia. Then, cFFR was obtained after intracoronary injection of 6 ml of contrast media, while FFR was measured after intravenous adenosine triphosphate administration (180 mcg/kg/min). Lesions with FFR less than or equal 0.80 were considered functional significance of coronary artery stenosis. Results: In 123 lesions, reference diameter, diameter stenosis, resting Pd/Pa ratio, cFFR, and FFR were 2.7±0.8 mm, 47±12%, 0.91±0.10, 0.83±0.12, and 0.81±0.12, respectively. Functional significance was observed in 41% of all lesions. Both of resting Pd/Pa and cFFR showed strong correlations with FFR (r=0.861, p<0.001, and r=0.930, p<0.001, respectively). The correlation coefficient of cFFR was significantly superior to that of resting Pd/Pa ratio (p<0.05). This strong correlation between cFFR and FFR was shown in every coronary artery (LAD; r=0.924, p<0.001, LCX; r=0.923, p<0.001, and RCA; r=0.926, p<0.001, respectively). The Bland-Altman plot demonstrated a good agreement with a mean difference of -0.02 and a standard deviation of 0.05 between cFFR and FFR across entire range of coronary artery stenosis. ROC curve analysis showed an excellent accuracy of cFFR <0.84 in predicting functional significance (AUC 0.96, sensitivity 90%, specificity 89%, and diagnostic accuracy 89%). Moreover, the cFFR >0.89 was not corresponded to functional significance of entire coronary artery stenosis. Conclusions: The cFFR is an accurate, rapid and easy method in predicting functional significance of entire coronary artery stenosis. This physiology-based approach may be a possible alternative method for FFR measurements in daily practice.