The purpose of this research is to assess safety and preliminary effectiveness of the Physician-Modified Terumo Treo Abdominal Stent-Graft System.

Inclusion Criteria:

• An aneurysm with a maximum diameter of >5.5cm in males and >5.0cm in females in diameter just proximal to the aneurysm using orthogonal (i.e., perpendicular to the centerline) measurements
• Aneurysm with a history of growth > 0.5 cm in 6 months
• Saccular aneurysm deemed at significant risk for rupture
• Symptomatic aneurysm
• Extent of aorta to be treated: type II, III and IV thoracoabdominal.
• Subject is at high-risk of morbidity and mortality with open surgical repair as defined by FEV1 of <1 liter or uncorrectable coronary disease, frailty, hostile abdomen.
• Iliac or femoral access vessel morphology that is compatible with vascular access techniques, devices or accessories, with or without use of a surgical conduit.
• Non-aneurysmal aortic segment proximal to the aneurysm (neck) with a:
• Minimum neck length of 15mm
• Diameter in the range of 17-32
• Minimum branch vessel diameter greater than 5 mm
• Iliac artery distal fixation site
• An inside diameter of 8mm - 13mm and a length of ≥ 10mm or
• an inside diameter of > 13mm - 20mm and a length of ≥ 15mm
• Age: ≥50 years old

Exclusion Criteria:

• Can be treated in accordance with the instructions for use with a legally marketed endovascular prosthesis
• Is eligible for enrollment in a manufacturer-sponsored IDE at the investigational site
• Unwilling to comply with the follow-up schedule
• Inability or refusal to give informed consent by subject or legal representative
• Subject is pregnant or breastfeeding
• Ruptured aneurysms
• Prior aortic repair
• Patient is eligible for treatment with an FDA-approved marketed device and patient can enroll in a manufacturer-sponsored clinical study at our institution or is willing and eligible to participate in a study with a manufacturer-made device at another institution.
• Known sensitivities or allergies to the materials of construction of the devices, including nitinol, polyester, PTFE, stainless steel, platinum/iridium, tantalum markers.
• Known hypersensitivity or contraindication to anticoagulation or contrast media that cannot be adequately medically managed
• Uncorrectable coagulopathy
• Body habitus that would inhibit x-ray visualization of the aorta or exceed the safe capacity of the equipment
• Subject has had a major surgical or interventional procedure unrelated to the treatment of the aneurysm planned < 30 days of endovascular repair
• Unstable angina (defined as angina with a progressive increase in symptoms, new onset at rest or nocturnal angina)
• Systemic or local infection that may increase the risk of endovascular graft infection
• Baseline creatinine greater than 2.0 mg/dL
• Thrombus or excessive calcification within the neck of the aneurysm
• Branch stenosis >50% not amenable to endovascular preparation