Assessment of fenestrated Anaconda stent graft design by numerical simulation: Results of a European prospective multicenter study

Objective: A crucial step in designing fenestrated stent grafts for treatment of complex aortic abdominal aneurysms is the accurate positioning of the fenestrations. The deployment of a fenestrated stent graft prototype in a patient-specific rigid aortic model can be used for design verification in vitro, but is time and human resources consuming. Numerical simulation (NS) of fenestrated stent graft deployment using the finite element analysis has recently been developed; the aim of this study was to compare the accuracy of fenestration positioning by NS and in vitro. Methods: All consecutive cases of complex aortic abdominal aneurysm treated with the Fenestrated Anaconda (Terumo Aortic) in six European centers were included in a prospective, observational study. To compare fenestration positioning, the distance from the center of the fenestration to the proximal end of the stent graft (L) and the angular distance from the 0 degrees position (C) were measured and compared between in vitro testing (L1, C1) and NS (L2, C2). The primary hypothesis was that Delta L (vertical bar L2 - L1 vertical bar) and Delta C (vertical bar C2 - C1 vertical bar) would be 2.5 or less mm in more than 80% of the cases. The duration of both processes was also compared. Results: Between May 2018 and January 2019, 50 patients with complex aortic abdominal aneurysms received a fenestrated stent graft with a total of 176 fenestrations. The Delta L and Delta C was 2.5 mm or less for 173 (98%) and 174 (99%) fenestrations, respectively. The NS process duration was significantly shorter than the in vitro (2.1 days [range, 1.0-5.2 days] vs 20.6 days [range, 9-82 days]; P<.001). Conclusions: Positioning of fenestrations using NS is as accurate as in vitro and could significantly decrease delivery time of fenestrated stent grafts.

Automated summary

The study compared the accuracy of fenestration positioning using numerical simulation and in vitro methods, showing that both methods were similarly accurate but numerical simulation had significantly shorter processing time.