Effectiveness and Safety of a Type A Dissection Total Endovascular Reconstruction System in Promoting Favorable Distal Aortic Remodeling

Effectiveness and Safety of a Type A Dissection Total Endovascular REconstruction System in Promoting Favorable Distal AOrtic ReModeling After Total Arch Replacement With Frozen Elephant Trunk for Type A Aortic Dissection: A Prospective, Multicenter, Randomized Controlled Trial

This is a prospective, multicenter, randomized controlled clinical study. A total of 198 eligible subjects will be enrolled and randomly assigned in a 1:1 ratio to either the Study Group or the Control Group. Subjects in the Study Group will receive surgical treatment using the study device (Type A Dissection Total Endovascular Reconstruction System) in addition to standard medical therapy following the Total Arch Replacement with Frozen Elephant Trunk. Subjects in the Control Group will continue standard medical therapy without surgical treatment using the study device following Total Arch Replacement with Frozen Elephant Trunk. Clinical follow-ups will be conducted at 30 days (±7 days), 6 months (±30 days), and 12 months (±30 days) post-enrollment to evaluate the effectiveness and safety of the study device.

After all subjects complete the 12-month (±30 days) follow-up, a statistical analysis will be performed and the results will be submitted for the study device registration application. Long-term follow-up will continue for 2-5 years post-enrollment.

Inclusion Criteria:

1. Age ≥18 years, male or female.

2. Within 90 days of onset of Stanford Type A Aortic Dissection and 30 days post Total Arch Replacement with Frozen Elephant Trunk treatment (assessed via CTA at 30±7 days post open surgery):

   1. Presence of any intimal tear in the residual dissection of the thoracic aorta and the false lumen is not completely thrombosed.
   2. The intercostal arteries in the segment of the residual thoracic aortic dissection are primarily supplied by the false lumen (number of intercostal arteries supplied by false/mixed lumen > number supplied by true lumen; only intercostal arteries filled with contrast agent are considered).
   3. False lumen volume in the thoracic aorta distal to the frozen elephant trunk stent graft is >50% of the total aortic lumen volume.

3. Voluntarily participate in this study and provide signed informed consent.

Exclusion Criteria:

1. Presence of a proximal anastomotic leak at the frozen elephant trunk site post open surgery.
2. No left subclavian artery revascularization during the open surgery.
3. Presence of severe endoleak, or residual dissection expansion ≥55mm, or distal stent graft-induced new entry.
4. History of myocardial infarction, or stroke (with clear symptoms/signs and culprit lesion), or bowel ischemia within 1 month prior to the procedure.
5. Previous history of descending thoracic or abdominal aortic surgery.
6. Lack of suitable vascular access.
7. Known allergy to components of the study device (e.g., Nitinol) or contrast agent.
8. Renal insufficiency (creatinine >2.5 times the upper limit of normal) or requiring long-term regular dialysis.
9. Severe liver dysfunction (Child-Pugh Class C).
10. Active bleeding, coagulation disorders, thrombocytopenia (platelet count <50×109/L), or refusal of blood transfusion.
11. Uncontrolled severe infection and associated sepsis, shock, or multiple organ failure.
12. Life expectancy less than 12 months (due to conditions other than aortic dissection).
13. Known or suspected connective tissue degenerative disease, or family history of aortic dissection.
14. Pregnant or lactating women.
15. Concurrent participation in other drug or medical device clinical studies.
16. Subjects deemed unsuitable for participating the study by the investigator.