Fig. 5

Boxplots for wall shear stress (WSS) parameters related to the formation of secondary flow patterns. WSS values at respective contours in the aorta are plotted against the grading of secondary flow patterns (Grad. FP) formed at the respective contour of the WSS measurement. In particular, the WSS gradient shows clearly increasing values with a higher grading of secondary flow patterns. While the influence of grade 1 flow patterns on all wall shear stress parameters is relatively small, the increase in WSS values in presence of grade 2 and grade 3 flow patterns is evident. The upper and lower borders of the box represent the upper and lower quartiles. The middle horizontal line represents the median, the upper and lower whiskers the maximum and minimum values of non-outliers. Outliers are marked as extra dots. Systematics of flow pattern grading is demonstrated in Fig. 3