# Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEM) of a Customized Stent-Graft for Endovascular (EVAR) Treatment of Abdominal Aortic Aneurism (AAA)

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## Abstract

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## 1. Introduction

- Diameter and length of the infrarenal aorta and neck of the aorta,
- Diameter and length of the iliac attachments,
- Tortuosity and size of the access vessels, and
- Critical vessel anatomy.

- Neck length ≥ 15 mm,
- Neck diameter < 30 mm,
- Neck angulation < 60–80 degrees, and
- Iliac diameter ≤ 7 mm.

## 2. Materials and Methods

- The blood flow was assumed incompressible and Newtonian with a density of 1060 $\mathrm{kg}/{\mathrm{m}}^{3}$ and viscosity of 0.003 $\mathrm{Pa}\ast \mathrm{s}$.

## 3. Results

## 4. Discussion

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 7.**(

**a**) Velocity inlet profile; (

**b**) pressure profile at abdominal outlet; (

**c**) pressure profile at mesenteric and branch1 outlets; (

**d**) pressure profile at branch2.

**Figure 9.**Wall shear stress at systole peak in (

**a**) Aneurismatic aorta, (

**b**) conventional graft, (

**c**) patient-specific graft.Reproduced with permission from S. Ragusa, K. Siciliano, F.P. Di Simone, S. Russotto, E. Bologna, M. Zingales, Theoretical and Applied Mechanics-Aimeta 2022; published by Centro Servizi d’Ateneo S.r.l., 2023.

**Figure 12.**Velocity in aneurysm site of three models. Reproduced with permission from S. Ragusa, K. Siciliano, F.P. Di Simone, S. Russotto, E. Bologna, M. Zingales, Theoretical and Applied Mechanics-Aimeta 2022; published by Centro Servizi d’Ateneo S.r.l., 2023.

Parameter | Description | Value |
---|---|---|

${E}_{a}$ | Austenite Young’ Modulus | 53,001 MPa |

${\nu}_{a}$ | Austenite Poisson’s Ration | 0.3 |

${E}_{m}$ | Martensite Young’ Modulus | 21.500 MPa |

${\nu}_{m}$ | Martensite Poisson’s Ration | 0.3 |

${\epsilon}_{t}$ | Transformation Strain | 0.038 |

${\sigma}_{L}^{s}$ | Start of Transformation Loading | 434 MPa |

${\sigma}_{L}^{e}$ | End of Transformation Loading | 500 MPa |

${\sigma}_{U}^{s}$ | Start of Transformation Unloading | 210 MPa |

${\sigma}_{U}^{e}$ | End of Transformation Unloading | 138.7 MPa |

${\sigma}_{CL}^{S}$ | Start of Transformation Stress in Compression | 434.0 MPa |

${\epsilon}_{V}^{L}$ | Volumetric Transformation Strain | 0.038 MPa |

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**MDPI and ACS Style**

Bologna, E.; Dinoto, E.; Di Simone, F.; Pecoraro, F.; Ragusa, S.; Siciliano, K.; Zingales, M.
Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEM) of a Customized Stent-Graft for Endovascular (EVAR) Treatment of Abdominal Aortic Aneurism (AAA). *Appl. Sci.* **2023**, *13*, 5712.
https://doi.org/10.3390/app13095712

**AMA Style**

Bologna E, Dinoto E, Di Simone F, Pecoraro F, Ragusa S, Siciliano K, Zingales M.
Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEM) of a Customized Stent-Graft for Endovascular (EVAR) Treatment of Abdominal Aortic Aneurism (AAA). *Applied Sciences*. 2023; 13(9):5712.
https://doi.org/10.3390/app13095712

**Chicago/Turabian Style**

Bologna, Emanuela, Ettore Dinoto, Francesco Di Simone, Felice Pecoraro, Sara Ragusa, Katia Siciliano, and Massimiliano Zingales.
2023. "Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEM) of a Customized Stent-Graft for Endovascular (EVAR) Treatment of Abdominal Aortic Aneurism (AAA)" *Applied Sciences* 13, no. 9: 5712.
https://doi.org/10.3390/app13095712