This study is about a medical device called the GORE® TAG® Conformable Thoracic Stent Graft with ACTIVE CONTROL System. It helps fix problems in the descending thoracic aorta, which is a big blood vessel in the chest. The study is observing people using this device over a long time, up to ten years. The goal is to see how well it works in the real world. It's called an observational study because doctors watch and record what happens without changing any treatments.

• The study lasts for up to ten years with regular follow-up visits.
• Participants must be 18 years or older and have used or plan to use the device.
• Participants cannot be in another new drug or device study during the first year.

People who want to join need to agree to be part of the study. It’s important for participants to be able to attend follow-up visits as planned. This study helps doctors learn more about how the device works over time and if it's a good treatment choice for patients.