Feasibility of Endovascular Repair Of Ascending Aortic Pathologies

The purpose of this study is to investigate the outcome of patients with pathologies of the ascending thoracic aorta (diseases in the great blood vessel or artery that leads away from the heart) including type A aortic dissection, retrograde type A aortic dissection, intramural hematoma, penetrating ulcer or pseudoaneurysm who are suitable for endovascular (within the vessel) repair with the Medtronic Valiant PS-IDE (Physician Sponsored-Investigational Device Exemption) Stent Graft. Type A aortic dissection is a condition where blood passes through the inner lining or between the layers of the blood vessel from a tear in the aortic wall (dissection) in the ascending aorta; a retrograde Type A aortic dissection is a condition where the dissection or tear in the ascending aorta starts from the descending aorta; an intramural hematoma is a collection of clotted blood within the aortic wall; a penetrating ulcer has a plaque or clot within the wall and a pseudoaneurysm is a false aneurysm . If left untreated in any of these conditions, the aorta can enlarge and rupture causing injury or death. The plan for these patients is to repair the ascending thoracic aorta using the Medtronic Valiant PS-IDE Stent Graft with the Captivia Delivery System. The Valiant Captivia has been evaluated worldwide and used extensively in patients with type B (descending) thoracic aortic dissection. Since the dissections in the ascending aortas mirror that of the descending aorta, it is expected that this stent graft will deliver similar performance and endurance in patients with type A aortic dissection. The investigators expect to reroute the blood to the true lumen (the inner space within the blood vessel) by covering the proximal (nearest to the heart) tear with the stent graft. The stent graft is a stent frame made from Nitinol wire and covered with an expandable material made of a polyester material. This new study will determine how well the device works to treat dissections, intramural hematomas, penetrating ulcers and pseudoaneurysms in the ascending thoracic aorta.