## 3 Results
### Flow Analysis
Post-operative remodelling each time increased aortic diameter in the true lumen (Figure 2). Uneven distribution of blood flow contours accompanied by a thinner aortic wall within the dissection area increased the risk of further aortic wall remodelling. Therefore, in all five cases, remodelling with insertion of an endograft in the aortic arch closed the false lumen and directed blood through the true channel that improved blood rheology. Furthermore, stent implantation led to an increased cross sectional diameter of the left renal artery, therefore ameliorating blood flow and decreasing pressure drag. The endovascular intervention separated the false lumen and directed blood flow through the true lumen leaving one channel. Post-operative remodelling each time increased blood velocity (Figure 3). Therefore, in all five cases, remodelling with insertion of an endograft in the renal artery improved blood rheology. The difference between clinical and the predicted velocity changes (mL/s) across the aortic branches according to Bland-Altman analysis was 0.17 mL/s (confidence interval equal to 2.76 mL/s). The separate analysis of blood flow changes in the adjacent branches relative to measured values were lower in the case of the thoracic artery (0.95 mL/s; confidence interval equal to 5.85 mL/s), the brachiocephalic trunk (0.01 mL/s; confidence interval equal to 0.89 mL/s) and the iliac arteries (0.10 mL/s; confidence interval equal to 0.55 mL/s), while higher values of calculated blood flow profiles were noticed for the carotid artery (0.02 mL/s; confidence interval equal to 0.74 mL/s) and the renal arteries (0.17 mL/s; confidence interval equal to 2.05 mL/s). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{6}{c}{**Blood Velocity [m/s]**} \\ \cline{2-6}
**Artery Type** & \multicolumn{3}{c}{**USG-Doppler**} & \multicolumn{3}{c}{**CFD**} \\ \cline{2-6}  & **Pre TEVAR** & **Post TEVAR** & **Pre TEVAR** & **Post TEVAR** & **Post TEVAR** \\  & **Median [Q1¡Q2]** & **Median [Q1¡Q2]** & **Median [Q1¡Q2]** & **Median [Q1¡Q2]** & **Median [Q1¡Q2]** & **_p_ Value** \\ \hline
**Thoracic trunk** & 0.273 & 0.223 & 0.043 & 0.321 & 0.217 & \(p\) = 0.043 \\  & (0.250,0.339) & (0.208,0.255) & (0.321,0.321) & (0.203,0.239) & \(p\) = 0.043 \\
**Renal arteries** & 0.315 & 0.343 & 0.324 & 0.355 & \(p\) = 0.043 \\  & (0.306,0.328) & (0.335,0.351) & \(p\) = 0.043 & (0.317,0.328) & (0.349,0.371) & \(p\) = 0.043 \\
**Iliac arteries** & 0.034 & 0.032 & 0.033 & 0.031 & \(p\) = 0.079 \\  & (0.034,0.035) & (0.031,0.034) & \(p\) = 0.079 & (0.032,0.035) & (0.031,0.031) & \(p\) = 0.079 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Changes in blood velocity [m/s] pre- and post-TEVAR for USG-Doppler and CFD. Data are presented as the median (Q1¡Q3). N = 5. _p_-values were calculated using the Wilcoxon Ranked Sign test. Figure 2: Changes in blood velocity contours of the aortic arch for a representative patient. (**top**) velocity contour distribution in the aortic arch for representative time points before and 7 months after TEVAR; (**bottom**) the average velocity changes for one cardiac cycle. Changes in velocity contours were presented for the anterior and posterior position in the aortic arch. Numerical simulations were calculated using ANSYS FLUENT software.