Effect of regional analysis methods on assessing the association between wall shear stress and coronary artery disease progression in the clinical setting

Much interest has been directed at understanding the role of hemodynamics, namely wall shear stress (WSS), in coronary artery disease (CAD) progression and vulnerable plaque formation. While advancements in invasive imaging and image-based modeling provide techniques to accurately predict the patient-specific hemodynamic environment, analysis methods to characterize the hemodynamic environment and evaluate the association between WSS and CAD progression vary considerably in the degree of spatial averaging. In a clinical cohort of 20 patients with moderate coronary atherosclerosis, we demonstrate that an increase in the spatial averaging of predicted hemodynamics across coronary territories leads to a reduction in the range of WSS values and distinct WSS classification patterns. Furthermore, we show that different CAD progression patterns stratified across WSS classifications result from the contrasting analysis methods and that local hemodynamic disturbances (e.g., regions of low and oscillatory WSS) and resulting plaque transformations can only be captured with focal analysis techniques. Future clinical studies that seek to determine the prognostic utility of WSS in the early identification of high-risk coronary lesions must remain cognizant of the consequences that analysis methods can have on the miscategorization and misrepresentation of coronary hemodynamics and resulting associations with CAD progression.