Midterm Outcomes of In Situ and In Vitro Fenestrated Stent-Grafts for Endovascular Repair of Aortic Arch Pathologies

Thoracic endovascular aortic repair (TEVAR) with fenestration technology for reconstruction of the aortic arch branches has been used in patients with aortic arch pathologies. However, the outcomes of comparisons between the 2 reconstruction methods are rarely reported. This study sought to compare and clarify the midterm outcomes between in situ and in vitro fenestrated stent-grafts for endovascular repair of aortic arch pathologies.

Between July 2016 and December 2023, the patients with aortic arch pathologies, who underwent TEVAR with in situ and in vitro fenestration grafts, were retrospectively evaluated. Endpoints included technical success, 30-day mortality, major adverse events, secondary interventions, target vessel patency, and overall survival.

A total of 46 patients (mean age 59 years; 40 males) with aortic arch pathology were included, each group (in situ and in vitro fenestration) with 23 cases. Technical success was 97.8% (45/46), and 1 patient died from severe pulmonary infection within 30 days. Perioperative major adverse events included stroke (n=3; 6.7%), spinal cord ischemia (SCI) (n=1; 2.2%). During a median follow-up of 40.8 months (IQR=57). The estimated all-cause overall survival rate was 97.8% (standard error [SE]=2.2%) and 84.5% (SE=6.7%) at 1 month and 48 months, respectively. The survival rate in the in situ group at 48 months was 95.5% (SE=4.4%) and the in vitro group was 74.2% (SE=11.7%). Log-rank test showed no significant difference (p=0.59). The overall branch arteries' primary patency was 97.8% (SE=2.2%) and 92.2% (SE=4.4%) in 1 month and 48 months. There was no significant difference between the 2 groups at 48 months (87.9% [SE=8.2%] for the in situ group, 95.7% [SE=4.3%] in the in vitro group [p=0.51]). The estimated freedom from secondary intervention was 100%, 90.2% (SE=4.7%), 84.0% (SE=6.1%), and 86.7% (SE=5.6%), at 1 month, 1 year, and 4 years. At 4 years, there was no significant difference in the estimated freedom from reintervention between the 2 groups (77.0% [SE=10.4%] for in situ group and 95.5% [SE=4.4%] in the in vitro group [p=0.33]).

For patients with aortic arch pathologies, in situ and in vitro fenestration techniques revealed comparable early and midterm results. Further evaluation of more patients with longer follow-up is needed to substantiate these results.Clinical ImpactOur single-center retrospective cohort study conducted a comparative analysis of in-situ fenestration versus in-vitro fenestration techniques in patients with aortic arch pathologies.Comparative studies between the two approaches are still limited. Our results provide a basis for the selection of in-situ or in-vitro fenestration techniques for endovascular repair of aortic arch lesion.