Comparative study of Japanese frozen elephant trunk device for open aortic arch repairs: assessment of mid-term outcomes

Structured Abstract: Objective We conducted a multicenter prospective comparative study to evaluate the impact of a Japanese frozen elephant trunk (FET) device in total arch replacement with FET (TARFET) compared with conventional replacement without FET (cTAR). The early outcomes in 684 patients treated between 2016 and 2019 have been reported; with 30-day mortality, cerebrovascular accident, and paraplegia rates of 0.8% (TARFET) vs. 0.3% (cTAR), 5.7% vs. 2.2%, and 1.6% vs. 0%, respectively. The present follow-up study focused on 3-year mid-term outcomes. Methods A total of 663 patients (354 TARFET and 309 cTAR) excluding 21 patients of early death or lost to follow-up were analyzed. Outcomes included mid-term mortality, aortic-related events, and computed tomography (CT) imaging findings, including true lumen diameter, false lumen thickness, and aneurysm sac diameter. Results Mid-term aortic-related mortality was similar (0.8% vs 1.3%, p=0.574), although all-cause mortality was lower in the TARFET group than in the cTAR group (6.5% vs 11.0%, p=0.039). Aortic-related events occurred more frequently after TARFET, including new-onset dissection (6.8% vs 4.5%, p=0.213), distal stent-induced new entry (3.7% vs 0%, p=0.023), repeated/additional aortic intervention (13.8% vs 5.8%, p=0.001)/ (6.2% vs 9.1%, p=0.166). CT imaging after TARFET demonstrated acceptable aneurysm shrinkage, and more favorable remodeling of the downstream descending aorta, including true lumen enlargement and false lumen regression, compared with cTAR. Conclusions Although mid-term all-cause mortality was lower in the TARFET group, aortic-related mortality was similar between the groups. TARFET was associated with favorable downstream aortic remodeling but also with an increased need for secondary aortic interventions.