The Medtronic Valiant Thoracoabdominal Stent Graft System is made up of two main body components and makes use of several off-the-shelf FDA-approved stent graft components. The two custom main body grafts are the thoracic bifurcation and the visceral manifold. The thoracic bifurcation is deployed in the thoracic aorta and provides the proximal seal for the device. For a Type I or II thoracoabdominal aneurysm the proximal seal is in zone 3, for Type III and V the device seals in zone 4, and for Type IV the device seals in zone 5. The two limbs of the thoracic bifurcation allows for continued aortic flow while deploying the visceral segment. The visceral manifold is deployed within the larger 20 mm limb of the thoracic bifurcation to set the stage for the visceral debranching. The branches of the visceral manifold extend to the visceral vessel with the use of covered bridging stents and provide distal seal of the manifold. The smaller 16 mm limb of the thoracic bifurcation extends to the infrarenal segment to either seal in zone 9 for a Type I and V and in zone 10 for Type II, III, and IV. All other connections in the device make use of sizes that are modular and independent of patient anatomy.