NCT07150559

Arch-Clamping Technique Under Mild Hypothermia in Treating With Acute Type A Aortic Dissection

Arch-Clamping Technique Under Mild Hypothermia in Treating With Acute Type A Aortic Dissection: Study Protocol for a Multicenter, Three-arm, Open-label, Randomized, Parallel-controlled Trial

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 306 (estimated)
• Sponsor: Beijing Anzhen Hospital · Academic / Other
• Sex: All
• Age: 18 Years – 70 Years
• Healthy volunteers: Not accepted

Summary

The study is a multicenter, three-arm, open-label, randomized, parallel-controlled trial, which plans to enroll 306 participants diagnosed with acute type A aortic dissection (ATAAD) from 7 hospitals in China. All patients receive total arch replacement (TAR) combined with frozen elephant trunk (FET) implantation and are randomized to Group 1 (arch-clamping technique under mild hypothermia), Group 2 (arch-clamping technique under moderate hypothermia) and Group 3 (Sun's procedure using bilateral antegrade cerebral perfusion) in the ratio of 1:1:1. After a 1-year follow-up, the validity and safety of the mild hypothermic arch-clamping technique for ATAAD was evaluated via the incidence of major adverse events including death, renal replacement therapy, stroke, and paraplegia, as well as times of circulatory arrest, cardiopulmonary bypass, and mechanical ventilation, and length of ICU stay.

Conditions

• Acute Type A Aortic Dissection
• Hypothermia
• Total Aortic Arch Replacement
• Frozen Elephant Trunk
• Bilateral Antegrade Cerebral Perfusion

Interventions

Type	Name	Description
PROCEDURE	Arch-Clamping Technique under Mild Hypothermia	This procedure is performed under mild hypothermia. The branch arteries of the arch are reconstructed using the side arms of a Y-shaped graft, which allows bilateral antegrade cerebral perfusion (bACP) through the right axillary artery. A FET is deployed in the descending aorta and clamped together with the autologous aorta immediately, then distal perfusion is restored through the femoral artery. After the proximal procedures are completed, the distal anastomosis is performed in an end-to-end fashion. Finally, the main trunk of the Y-shaped graft is anastomosed to the proximal grafts.
PROCEDURE	Arch-Clamping Technique under Moderate Hypothermia	This procedure is performed under moderate hypothermia. The branch arteries of the arch are reconstructed using the side arms of a Y-shaped graft, which allow bACP through the right axillary artery. A FET is deployed in the descending aorta and clamped together with the autologous aorta immediately, then distal perfusion is restored through the femoral artery. After the proximal procedures are completed, the distal anastomosis is performed in an end-to-end fashion. Finally, the main trunk of the Y-shaped graft is anastomosed to the proximal grafts.
PROCEDURE	Total Arch Replacement combined Frozen Elephant Trunk Implantation using Bilateral Antegrade Cerebral Perfusion under Moderate Hypothermic Circulatory Arrest	This procedure is performed using bACP under MHCA, which involves FET deployment in the descending aorta followed by total arch replacement with a four-branched vascular graft. Deployment of the FET and suture of the distal anastomosis are completed during bACP. MHCA is terminated and distal reperfusion is initiated once the distal anastomosis is completed, and the left carotid artery is reconstructed first (after which bACP is stopped, rewarming is started and the brain is perfused bilaterally). The root or valve procedures and some concomitant operations, if indicated, are performed during the cooling phase.

Timeline

• Start date: 2026-02-03
• Primary completion: 2027-12-30
• Completion: 2028-02-28
• First posted: 2025-09-02
• Last updated: 2026-04-06

Locations

1 site across 1 country: China