AUTHOR=Ho Nghia Nguyen , Lee Kwan Yong , Lee Sang-Wook TITLE=Uncertainty quantification of computational fluid dynamics-based predictions for fractional flow reserve and wall shear stress of the idealized stenotic coronary JOURNAL=Frontiers in Cardiovascular Medicine VOLUME=Volume 10 - 2023 YEAR=2023 URL=https://www.frontiersin.org/journals/cardiovascular-medicine/articles/10.3389/fcvm.2023.1164345 DOI=10.3389/fcvm.2023.1164345 ISSN=2297-055X ABSTRACT=In clinical practice, hemodynamics-based functional indices, such as fractional flow reserve (FFR) and wall shear stress (WSS), are useful in assessing the severity and risk of rupture of atherosclerotic lesions. Computational fluid dynamics (CFD) is widely used to predict these indices noninvasively. In this study, uncertainty quantification and sensitivity analysis are performed for the computational prediction of WSS and FFR directly from 3D-0D coupled CFD simulations on idealized stenotic coronary models. Five geometric parameters (proximal, mid, and distal lengths of stenosis; reference lumen diameter; and stenosis severity) and two physiological parameters (mean aortic pressure and microcirculation resistance) are considered as uncertain input variables. The degree of stenosis and the mean aortic pressure exhibited highest sensitivity to variations in the computed WSS. When employing the true values of stenosis severity and mean aortic pressure, a discernible reduction of 25% and 9.5% in the uncertainty of the computed proximal WSS, respectively. In addition, degree of stenosis, reference lumen diameter, and coronary resistance are the primary contributors to the uncertainty of computed FFR, accounting for 41.2%, 31.9%, and 24.6%, respectively. In particular, the interactive effect of the input variables on the uncertainty of the computed WSS is significantly higher than that on the uncertainty of the computed FFR.