Late outcomes of the frozen elephant trunk technique for acute and chronic aortic dissection: the angle change of the FROZENIX by "spring-back" force.

Objectives: To evaluate the outcomes of total arch replacement using the frozen elephant trunk technique with a FROZENIX J Graft for patients with either acute or chronic aortic dissection, and to evaluate the late-phase outcomes.

Methods: Between January 2015 and December 2020, we used the frozen elephant trunk technique in 47 patients with acute aortic dissection and 12 patients with chronic aortic dissection. The primary endpoints were 30-day mortality, late aorta-related death and late aortic events. The secondary endpoints included early surgical complications and any aortic events (e.g. stent graft-induced new entry, frozen elephant trunk angle change).

Results: In the acute group, there were no aorta-related deaths, although 13 patients (27.7%) experienced an aortic event; stent graft-induced new entry occurred in 6 patients (12.8%). In the chronic group, 1 patient (9.1%) experienced aorta-related death, and 9 (81.8%) experienced an aortic event; stent graft-induced new entry occurred in 4 patients (36.4%). During the late phase after surgery, there was a significant increase in the frozen elephant trunk angle in both groups. In the AAD group, both the FET angle and spring-back angle were significantly enlarged in the late phase. There were no significant differences between groups in the degree of angle change, the overall survival, or aortic event-free survival.

Conclusions: Total arch replacement using the frozen elephant trunk technique affords good early-stage results for both acute and chronic aortic dissection. During follow-up, careful monitoring for aortic events and appropriate therapeutic interventions are required. If surgeons are to use this device, they must have a thorough understanding of its spring back force and other features.