In patient-specific simulations of coronary arteries, time-averaged wall shear stress was highly correlated between elastic and rigid wall models (r = 0.99) with no significant differences, justifying the use of rigid wall models.
Does the use of elastic wall models compared to rigid wall models significantly alter time-averaged wall shear stress calculations in CCTA-based coronary simulations?
Patient-specific coronary hemodynamic simulations using rigid wall models yield time-averaged wall shear stress results highly correlated with elastic models, justifying the use of simpler rigid models in future studies.
Effect estimate: r = 0.99
Absolute Event Rate: 16% vs 15.6%
p-value: p=0.5
Wall shear stress (WSS) has been shown to be associated with myocardial infarction (MI) and progression of atherosclerosis. Wall elasticity is an important feature of hemodynamic modeling affecting WSS calculations. The objective of this study was to investigate the role of wall elasticity on WSS, and justify use of either rigid or elastic models in future studies. Digital anatomic models of the aorta and coronaries were created based on coronary computed tomography angiography (CCTA) in four patients. Hemodynamics was computed in rigid and elastic models using a finite element flow solver. WSS in five timepoints in the cardiac cycle and time averaged wall shear stress (TAWSS) were compared between the models at each 3 mm subsegment and 4 arcs in cross sections along the centerlines of coronaries. In the left main (LM), proximal left anterior descending (LAD), left circumflex (LCX), and proximal right coronary artery (RCA) of the elastic model, the mean percent radial increase 5.95 ± 1.25, 4.02 ± 0.97, 4.08 ± 0.94, and 4.84 ± 1.05%, respectively. WSS at each timepoint in the cardiac cycle had slightly different values; however, when averaged over the cardiac cycle, there were negligible differences between the models. In both the subsegments (n = 704) and subarc analysis, TAWSS in the two models were highly correlated (r = 0.99). In investigation on the effect of coronary wall elasticity on WSS in CCTA-based models, the results of this study show no significant differences in TAWSS justifying using rigid wall models for future larger studies.
Eslami et al. (Fri,) conducted a other in Coronary artery disease with moderate stenosis (n=4). Elastic wall modeling (Fluid-Structure Interaction) vs. Rigid wall modeling was evaluated on Time-averaged wall shear stress (TAWSS) across 3 mm subsegments (r = 0.99, p=0.5). In patient-specific simulations of coronary arteries, time-averaged wall shear stress was highly correlated between elastic and rigid wall models (r = 0.99) with no significant differences, justifying the use of rigid wall models.