## 3 Results and Discussion  
### CFD Analysis  
The conducted CFD analyses sufficiently simulated the flow field inside the examined aorta arteries, evaluating their main physical quantities, such as flow's pressure distribution and flow's velocity magnitude, as it is depicted in Figure 5. Furthermore, via CFD analyses, the main indicators that show abnormalities in the flow, such as pressure losses, energy losses, and mass flow, were accurately calculated, quantifying the size of the cardiovascular \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Material** & **Density** & **Elastic Modulus** & **Tensile** & **Elongation at** \\  & **[g/cm\({}^{3}\)]** & **[MPa]** & **Strength [MPa]** & **Break [\%]** \\ \hline Heart tissue & 1.055 & 2.84 & 0.19 & - \\ RWT-ENT A50 & 1.128 & 3.56 & 0.53 & 65 \\ Visijet CE-NTT(tm) & 1.120 & 0.35 & 0.3 & 195 \\ Visijet CR-CL 200 TM & 1.160 & 1750 & 36.5 & 18 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Main elastic properties of the employed materials. problem. It is worth mentioning that an aorta without the defect was used as a benchmark of how blood flow should have been in case the CoA defect was eliminated. More specifically, Figure 5a portrays the employed CFD model and Figure 5b portrays the pressure distribution for the aorta with a CoA defect on the left side and the normal one on the right side. The pressure inside the examined aorta's model ranges between 60 mmHg to 140 mmHg, with the nominal mean pressure for the non-defected aorta set at 100 mmHg, leading to an intense fluctuation concerning the developed pressure values. In addition, in the CoA case, a high-pressure region occurred in the ascending aorta with pressure values from 120 mmHg to 140 mmHg due to the severe stenosis of the artery at the beginning of the descending aorta. As expected, a rapid drop in the pressure (around 70 mmHg) in the stenosis region resulted in discontinuities in the blood flow. On the other hand, the aorta without any defect revealed a more uniform pressure distribution within the flow field, with values ranging between 80 mmHg to 130 mmHg. It is noteworthy that only a few individual peaks of pressure (130 mmHg) occurred at specific stagnation points of the blood flow due to the aorta's morphology. Figure 5c shows the developed velocity magnitudes for the investigated aortas. The aorta with the stenosis revealed extensive and rapid changes in blood flow velocity ranging from 0 m/s to 3 m/s. In addition, the increased pressure in the ascending aorta caused an increase in the velocity of the outlet vessels, and the rapid changes in the flow pressure led to flow separation right before the stenosis, thus disrupting the flow and triggering turbulence phenomena. Moreover, in the stenosis region, a maximum velocity of almost 3 m/s was observed with a 'high velocity' flow jet (around 1.5 m/s) after the stenosis in the left side of the artery, resulting in significant flow recirculation and an increase in the turbulence flow. In contrast, the aorta without the defect presented a uniform velocity magnitude, with values ranging between 0.35 m/s to 2.1 m/s. The observed flow in the descending aorta was mainly laminar, with only minor flow separations due to the non-uniform geometry of the artery. Taking into account the aforementioned analysis, it is obvious that the investigated CoA case caused a significant disruption of the blood flow inside the aorta, with intense  
Figure 5: (**a**) Applied CFD model, (**b**) pressure distribution, and (**c**) velocity magnitude for the aorta with CoA coupled with superimposed images of the stenosis (**left**) and for the aorta without CoA (**right**). flow separations, flow recirculation, and turbulence insertion.