∙ The patient must have one of the following:

• Degenerative, atherosclerotic thoracoabdominal, suprarenal and juxtarenal aortic aneurysms (fusiform or saccular):≥55mm in diameter in a male or ≥50mm in diameter in a female, or

• Thoracoabdominal aortic aneurysm with a history of growth ≥0.5 cm per year, or

• Penetrating ulcers: ≥20mm in depth or

• Chronic type B aortic dissections: ≥50mm total aortic diameter or

• Symptomatic pathology (aneurysm, ulcer or chronic dissection) of any size.

∙ Additional criteria for LP material

∙ • Iliofemoral access vessels \<8mm or with significant atherosclerotic occlusive disease that would require an iliac conduit as determined by the Principle Investigator

∙ The subject must have one of the following:

• Degenerative, atherosclerotic aneurysm involving the ascending aorta, aortic arch or proximal descending aorta ≥55 mm in diameter or \> 50 mm with a history of growth ≥5 mm in the last 6 months, or

• Penetrating ulcers: ≥20 mm in depth, or

• Chronic aortic dissections: ≥50mm total aortic diameter. AND Prohibitive or high-risk for standard open surgical repair, defined as having one or more of the following pre-existing conditions.

‣ Age \>85 years old.

⁃ Prior median sternotomy (for any reason).

⁃ Prior open or endovascular thoracic aortic repair.

⁃ Severe aortic calcification.

⁃ Severe occlusive disease of one or more arch vessels.

⁃ Moderate-severe COPD (FEV1 \<80% predicted).

⁃ Severe CKD (Stage 3 or greater, eGFR \<60 mL/min).

⁃ LV dysfunction.

⁃ Chronic steroid or immunosuppressive use.

‣ History of increased risk of bleeding.

‣ Neurocognitive deficits that may significantly impact postoperative rehabilitation.

‣ Musculoskeletal conditions that may significantly impact postoperative rehabilitation.