Bridging stent graft fracture after branched endovascular aortic repair in a dual-center retrospective cohort study

Objective: Target vessel instability is a relevant complication after thoracoabdominal aortic aneurysms branched endovascular aortic repair (BEVAR). Long-term bridging stent graft (BSG) durability has already been established, but the incidence of long-term complications as component fractures was not deeply investigated. This paper aims to assess BSG fracture incidence and risk factors after BEVAR. Methods: This was a dual-center observational retrospective cohort study. Data of each patient treated with BEVAR between April 2008 and December 2019 were prospectively collected. The primary outcome was the incidence of BSG fracture during follow-up. A logistic regression analysis was performed, including preoperative and postoperative measurements as well as intraoperative details to identify potential risk factors. Results: Two hundred ninety-five target visceral vessels in 91 patients were considered suitable for cannulation. Technical success was 96.9% (286/295 target visceral vessels). The median follow-up was 32.5 months (interquartile range, 14.3-50.1 months). Five BSG fractures (1.75%; 5/286) were detected. Four BSG fractures involved the superior mesenteric artery, and one the celiac trunk. Four different types of fractured stents were detected during follow-up: two Advanta, one BeGraft, one Fluency, and one Viabahn. The median time to BSG fracture was 28.2 months (interquartile range, 11.7-50.8 months). The use of multiple stents (P = .030) and different stent types on the same vessel (P = .004) were associated with BSG fracture at univariable analysis. Using bare-metal stents for distal relining (P = .045) was the only significant factor predisposing to BSG fracture at multiple logistic regression. Conclusions: BSG fracture is a rare but severe complication after BEVAR. It is not related to the stent type used as bridging stent, and it is hardly predictable based on preoperative anatomy. Using multiple and different stents on the same vessel and relining the bridging stents with bare-metal stents may increase BSG fracture risk. A strict computed tomography angiography follow-up remains the best strategy to detect target vessel instability.