Single-center retrospective cohort study on long-term outcomes of Zone 1 arch repair with frozen elephant trunk using Frozenix: up to 9.5 years of follow-up.

BACKGROUND

Zone 1 aortic arch repair using the frozen elephant trunk (FET) technique is critical for treating thoracic aortic diseases like aortic aneurysm (AA) and aortic dissection (AD). Although FET offers promising outcomes, the long-term benefits, risks, and re-intervention rates, particularly for Zone 1 repairs, remain areas of active investigation. This study evaluates the long-term outcomes of using the Frozenix Open Stent-Graft for this procedure.

METHODS

This single-center retrospective cohort study analyzed 353 patients who underwent Zone 1 aortic arch repair with the Frozenix Open Stent-Graft from July 2014 to December 2023. Primary endpoints included in-hospital mortality, follow-up survival, and complications; the secondary endpoint was aortic re-intervention. Patients received computed tomography (CT) scans pre-operatively, at discharge, annually, and as needed. Survival was analyzed with the Kaplan-Meier method, and re-intervention incidence was evaluated using a competing risk analysis, with death as a competing event.

RESULTS

The study included patients with a mean age of 71.4±11.2 years, of whom 72.8% were male. The cohort included 159 AA and 194 AD cases. The follow-up period had a median duration of 2.1 years, with an interquartile range of 0.8 to 4.5 years. The maximum follow-up was 9.5 years, and the minimum was 0.06 years. The 30-day mortality rate was 2.8%, with a late mortality rate of 15.6%. Major complications included stroke (9.9%) and spinal cord injury (2.0%). Survival rates at 1, 3, and 5 years were 88.9%, 82.6%, and 76.2%, respectively. Survival analysis revealed significant differences among aortic pathologies (P=0.001), with acute AD showing the best outcomes. During follow-up, 65 re-interventions were performed (39 endovascular, 26 open surgeries). The cumulative incidence of re-intervention at 1, 3, and 5 years was 8.9%, 15.3%, and 24.3%, respectively. Notably, patients who underwent re-intervention demonstrated significantly better survival than those who did not (P<0.001).

CONCLUSIONS

Zone 1 aortic arch repair using the Frozenix Open Stent-Graft shows promising long-term results with acceptable mortality and complication rates. The procedure appears to be particularly effective for acute ADs. The higher survival rate in the re-intervention group suggests that careful follow-up and timely re-intervention may improve long-term outcomes. These findings underscore the importance of lifelong surveillance and readiness for potential re-interventions in managing patients with complex aortic pathologies.