Abstract 16197: Comparison of Optical Coherence Tomography-Derived Parameters With Fractional Flow Reserve for Assessment of Coronary Artery Stenosis
Backgrounds; Fractional flow reserve (FFR) and intravascular imaging respectively provide functional, anatomical, and morphological assessments of angiographic intermediate stenosis. Optical coherence tomography (OCT) is a promising high-resolution imaging modality, but its clinical use in determining severity of coronary disease has yet to be determined. We assessed OCT criteria for predicting functional significance of coronary stenoses, and compared OCT findings between the two groups with or without significant functional stenosis.
Methods and Results; Twenty-eight lesions underwent OCT and FFR assessment before intervention. FFR was measured at maximal hyperemia induced by intravenous adenosine triphosphate(160µg/kg/min). FFR<0.80 at maximum hyperemia was seen in 20 patients (71%). OCT morphological analyses included the presence of lipid-rich plaques, thin-capped fibroatheroma (TCFA), fibrous cap thickness, and presence of plaque rupture. When a plaque contained 2 or more lipid-containing quadrants, it was considered a lipid-rich plaque, while a TCFA was defined as a lipid-rich plaque with a fibrous cap thickness of <70μm. OCT anatomical parameters included minimal lumen area (MLA) and lumen volume (LV/cm). There was no differences in morphological findings between the lesions with or without FFR <0.8(lipid-rich plaques 55% vs 87.5%, TCFA 20% vs 12.5%, cap thickness 141.7 vs 133.5, plaque rupture 0% vs 25%, p=ns). Receiver operating characteristic (ROC) curve analyses revealed that the best cut-off values of MLA and LV for discriminating the lesions with FFR<0.8 were 1.01mm2 (AUC 0.806, sensitibity 83.3%, specificity 88.9%, diagnostic accuracy 84.8%, p=0.0008) and 26.78mm3 (AUC 0.819%, sensitibity 66.7%, specificity 88.9%, diagnostic accuracy 72.7%, p=0.0001).
Conclusion; No difference in morphological instability by OCT was observed between the groups with or without FFR<0.8 in the present cohort. The present study suggests a potential role of OCT for functional, anatomical, and morphological assessment to guide decision making in intervention.
- © 2011 by American Heart Association, Inc.