The objective of this study is to determine whether the GORE® TAG® Thoracic Branch Endoprosthesis is safe and effective in treating lesions of the aortic arch and descending thoracic aorta.

For Zone 0/1, there are two arms (Aneurysm arm, Non-aneurysm arm) and three cohorts, described as follows: Zone 0/1 Aneurysm, Zone 0/1 Dissection, and Zone 0/1 Other Isolated Lesion. The Zone 0/1 Aneurysm cohort was the only cohort analyzed with a hypothesis test, however data was collected similarly for all cohorts and for continued access Subjects. Zone 0/1 Subjects enrolled for analysis were from the United States and Japan.

Inclusion Criteria:

1. Presence of thoracic aortic pathology deemed to warrant surgical repair which requires proximal graft placement in Zone 0-2.
2. Age ≥18 years at time of informed consent signature
3. Subject is capable of complying with protocol requirements, including follow-up
4. Informed Consent Form (ICF) is signed by Subject or legal representative
5. Must have appropriate proximal aortic landing zone.
6. Must have appropriate target branch vessel landing zone.
7. For patients with aneurysm/isolated lesion, must have appropriate distal aortic landing zone.
8. Native aortic valve (Zone 0/1 subjects only)
9. Subject is considered a high risk candidate for conventional open surgical repair at the discretion of the Investigator (Zone 0/1 subjects only)

Exclusion Criteria:

1. Concomitant disease of the ascending aorta or aneurysm of the abdominal aorta requiring repair
2. Previous endovascular repair of the ascending aorta
3. Previous endovascular repair of the DTA with a non-Gore device
4. Surgery within 30 days prior to enrollment, with the exception of surgery for Ascending Aortic Dissection and/or placement of vascular conduit for access.
5. Infected aorta
6. Life expectancy <2 years
7. Myocardial infarction within 6 weeks prior to treatment
8. Stroke within 6 weeks prior to treatment, stroke defined as rapidly developing clinical signs of focal (or global) disturbance of cerebral function, lasting more than 24 hours or leading to death, with no apparent cause other than that of vascular origin.
9. Patient has a systemic infection and may be at increased risk of endovascular graft infection
10. Pregnant female at time of informed consent signature
11. Degenerative connective tissue disease, e.g. Marfan's or Ehler-Danlos Syndrome
12. Participation in another drug or medical device study within one year of study enrollment
13. Known history of drug abuse within one year of treatment
14. Presence of protruding and/or irregular thrombus and/or atheroma in the aortic arch or ascending aorta
15. Tortuous or stenotic iliac and/or femoral arteries preventing introducer sheath insertion and the inability to use a conduit for vascular access
16. Planned coverage of celiac artery
17. Patient has known sensitivities or allergies to the device materials
18. Patient has known hypersensitivity or contraindication to anticoagulants or contrast media, which is not amenable to pre-treatment
19. Previous instance of Heparin Induced Thrombocytopenia type 2 (HIT-2) or known hypersensitivity to heparin
20. Patient with a history of a hypercoagulability disorder and/or hypercoagulability state
21. Diameter taper outside of the device sizing range between proximal and distal landing zones of aorta and the inability to use additional devices of different diameters to compensate for the taper
22. Mycotic aneurysm
23. Persistent refractory shock (systolic blood pressure <90 mm Hg)
24. Patient has body habitus or other medical condition which prevents adequate visualization of the aorta
25. Renal failure defined as patients with an estimated Glomerular Filtration Rate (eGFR) <30 or currently requiring dialysis
26. Patient at high risk of neurological event, e.g. stroke