Stress on Aortic Aneurysms

1
Stress on Aortic Aneurysms

• University of Rhode Island
• Biomedical Engineering
• Kasey Tipping

2
Overview

• What/Where/ Why/ Who
• How is it diagnosed?
• Treatment
• Surgery
• Benefits of a 3-Dimensional Model
• Effects of the Study
• Sources

3
What?

• Aorta The largest artery in the body, extends
  from the heart to the lower abdomen
• Aneurysm localized blood filled dilation, causes
  weakening of the artery wall If this occurs
  it causes discomfort, could rupture
  (severe pain) in which case death could
  result

4
Where?

• The aneurysms occur in the thoracic and
  abdominal regions (90) of the aorta
• Abdominal Start off as asymptomatic, leads to
  pain in the abdomen
  and back (AAA)
• Thoracic more evident,
• chest pain, cough, shortness of
  breath
• Tend to be spindle shaped

5
Why?

• Arterioclerosis hardening of the arteries (80)
  
• Post-trauma physical trauma to aorta
• Genetic disease/ hereditary rare inheritable
  disease of connective tissue (Ehlers-Danlos or
  Marfans)
• Infection syphilis or endocarditis
• Risk factors
• Smoking, high blood pressure, high cholesterol,
  age

6
How is it Diagnosed?

• MRI, Ultrasound, CT scan
• Treatment
• Larger Aneurysms (gt5.5cm)
• Surgery physically capable or whether it can be
  postponed
• Smaller Aneurysms (lt5.5cm)
• Beta blockers (high blood pressure and
  cholesterol meds)
• Both No smoking, exercise, heart-healthy diet

7
Surgery

• Open heart surgery
• Major surgery
• Low to average risk patients
• Sewing in a synthetic tube
• Endovascular Stent Graft
• Minimally invasive
• Guiding a wire carrying a catheter from the
  femoral artery to the aneurysm, and a fabric tube
  is fitted in place to reinforce the walls

8
Benefits of a 3-Dimensional Model Peak wall
stress Rupture point 2-D 3-D
9
The Study

• 5 patients with AAA
• Three constitutive models two anisotropic (
  12) and one isotropic
• Used to model the mechanical behavior of the
  aneurysmal wall
• CT scan, calculations, MATLAB, outcome

10
Results

• Isotropic Anisotropic (1) Anisotropic (2)
  Isotropic Anisotropic (1) Anisotropic (2)

11
Work Cited

• Works Cited
• -The Effect of Material Model Formulation in the
  Stress Analysis of Abdominal
• Aortic Aneurysms 37.11 (09) 2218-221. Print.
• -Aortic Aneurysm. Yahoo Heart Vascular Health,
  2010. Web. 17 Feb. 2010.
• -Aortic Aneurysm. WebMd, 2010. Web. 18 Feb. 2010.
  
• -Aortic Aneurysms. The Society of Thoracic
  Surgeons, 2010. Web. 16 Feb. 2010.