The Impact of the Right Coronary Artery Geometric Parameters on Hemodynamic Performance.

Abstract

Coronary artery geometry can have a significant impact in the hemodynamic behavior of coronary blood flow, influencing atherosclerotic plaque formation. The present work focuses on, through a statistical study, the connection between several geometric parameters of the right coronary artery-ostium cross-sectional area, angles between the common trunk and the side-branches, tortuosity, curvature and cross-sectional area in each side-branch-and their influence on hemodynamic descriptors. Parameters such as low wall shear stress and local disturbed flow, which are associated with atherosclerosis formation, were analysed. Computed tomography images of ten healthy individuals were selected to reconstruct in vivo three-dimensional models of right coronary arteries. Blood flow was simulated through a compliant model with realistic boundary conditions. Calculated hemodynamic descriptors values were correlated with the geometric parameters using the Pearson correlation coefficient (r) and the p value. The strongest correlations were found in the middle and distal segments of the right coronary artery. A decrease in the ostium area promotes a decrease in the WSS magnitude from the proximal to the distal segment (r = 0.82). Very strong correlations (r > 0.90) were achieved between geometric parameters (cross-sectional area, angle, tortuosity) of the right-ventricular branch and the wall shear stress magnitude in the middle and distal segments. Low values of tortuosity, smaller cross-sectional area and higher angle of the right-ventricular branch leads to a hemodynamic behavior more propitious to atherosclerosis formation, within the study cases. The right-ventricular branch seems to have the highest influence in the hemodynamic behavior of the right coronary artery.