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 Marfan’s) 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 (>5.5cm) Surgery: physically capable or whether it can be postponed Smaller Aneurysms (<5.5cm) 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-D3-D

9. The Study 5 patients with AAA Three constitutive models: two anisotropic ( 1&2) 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)

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.