Physician-modified Endovascular Graft for Repair of Complex Thoracoabdominal and Abdominal Aortic Aneurysms

Inclusion Criteria: 1. Age ≥ 18 years old 2. Life expectancy \> 2 year(s) 3. Patient is considered to be at high risk of morbidity and mortality with open surgical repair 4. A patient may be entered into the study if the patient has at least one of the following: * Juxtarenal, suprarenal or a thoracoabdominal aortic aneurysm with a diameter ≥ 5.5 cm or 2 times the normal aortic diameter * Aneurysm with a history of growth ≥ 0.5 cm per year * Saccular aneurysms deemed at significant risk for rupture based upon physician interpretation * Symptomatic juxtarenal, suprarenal or a thoracoabdominal aortic aneurysm * Thoracoabdominal aortic aneurysms secondary to aortic dissection meeting above criteria 5. Patient is considered to be at high risk of morbidity and mortality with open surgical repair 6. Iliac or femoral access vessel morphology that is compatible with vascular access techniques, devices or accessories, with or without use of a surgical conduit 7. Nonaneurysmal aortic segment proximal to the aneurysm (neck) with a: * Minimum neck length of 20mm * Diameter in the range of 21-38mm * Angle less than 60° relative to the axis of the aneurysm * Angle less than 60° relative to the axis of the suprarenal aorta 8. Minimum branch vessel diameter greater than 5 mm 9. Iliac artery distal fixation site greater than 10mm in length and diameter in the range of 8-21mm. Exclusion Criteria: 1. Under the age of 18 years 2. Can be treated in accordance with the instructions for use with a legally marketed endovascular prosthesis 3. Is eligible for enrollment in a manufacturer-sponsored IDE at the investigational site 4. Willing to participate in a sponsor-investigator IDE with access to a non-physician modified endovascular prostheses at the investigational site 5. Willing to travel to an investigational site with access to a non-physician modified endovascular prosthesis 6. Unwilling or unable to comply with the follow-up schedule 7. Inability or refusal to give informed consent by patient or legal representative 8. Patient is pregnant or breastfeeding 9. Life expectancy \< 2-years despite successful aneurysm exclusion 10. Free rupture with hemodynamic instability 11. Ongoing infection 12. Diagnosis of, or suspected connective tissue disease 13. Known sensitivities or allergies to the materials of construction of the devices 14. Known hypersensitivity or contraindication to anticoagulation or contrast media that cannot be adequately medically managed 15. Uncorrectable coagulopathy 16. Body habitus that would inhibit x-ray visualization of the aorta or exceeds the safe capacity of the equipment 17. Patient has had a major surgical or interventional procedure unrelated to the treatment of the aneurysm planned ≤ 30 days of the endovascular repair 18. Unstable angina (defined as angina with a progressive increase in symptoms, new onset at rest or nocturnal angina) 19. Systemic or local infection that may increase the risk of endovascular graft infection 20. Leaking or free rupture of aneurysm associated with hemodynamic instability. 21. Baseline creatinine greater than 3.0 mg/dL 22. Known history of, or suspected connective tissue disorders (e.g., Marfan Syndrome, Ehler's Danlos Syndrome) Anatomical exclusion criteria: 1. Inadequate femoral or iliac access compatible with the required delivery systems, not amenable to open surgical or endovascular conduit placement 2. Absence of a non-aneurysmal aortic segment for proximal seal zone with: * A diameter measured outer wall to outer wall of no greater than 38mm and no less than 21 mm; * Parallel aortic wall with \<20% diameter change and without significant calcification and/or thrombus in the selected area of seal zone 3. Visceral vessel anatomy not compatible with physician-modified Zenith® Alpha Endovascular Graft due to excessive occlusive disease or small size not amenable to stent graft placement 4. Unsuitable distal iliac artery fixation site and anatomy: * Common iliac artery fixation site diameter measured outer wall to outer wall on a sectional image (CT) \<8.0 mm with inability to perform open surgical conduit * Iliac artery diameter measured outer wall to outer wall on a sectional image (CT) \>21 mm at distal fixation site, with inability to perform open internal iliac artery revascularization or iliac branch stent graft * Iliac artery distal fixation site \<10 mm in length * Inability to preserve at least one hypogastric artery