Bridging Stents in Fenestrated and Branched Endovascular Aneurysm Repair: A Systematic REVIEW

Background: Concern exists about durability of stent grafts used to bridge aortic grafts to visceral and renal arteries during fenestrated and branched endovascular aneurysm repair (F/ B-EVAR). There are no guidelines regarding the ideal technique for joining target vessels (TVs). Methods: We systematically reviewed data published from 2014 to 2019 using PRISMA guidelines and PICO models. Keywords were searched in MEDLINE, EMBASE, and Cochrane Library. All articles were screened by two authors (a third author in case of discrepancies). Only original articles regarding F/B-EVAR in complex aortic aneurysm, reporting the number and type of TVs mated, the onset of bridging stent complications, and reinterventions on TVs were included. Analysis included quality assessment scoring, types of stent grafts, and complications related to bridging stents. Results: 19 studies were included with 2,796 patients and 9556 TV; 4,797 renal arteries (50.2%), 4,174 visceral arteries (43.6%), and undefined TV (n = 585; 6.1%) were bridged. Balloon-expandable stent-grafts (B-EXP) were used in 40.9% and self-expandable (S-EXP) in 22.7% and undefined stents in 36.3%. The included studies had quality assessment scores ranging between 11/15 and 15/15, with high grade of accordance on reporting general results, but a low grade of accordance on reporting detailed data. Despite study heterogeneity, highvolume analysis confirmed a higher rate of complication in renal arteries than visceral arteries, 6% (95% CI 4-8) vs. 2% (95% CI 1-3), respectively. The rate of reinterventions was similar, 3% (95% CI 2-4) and 2% (95% CI 1-3). S-EXP versus B-EXP stent complication was 4% (95% CI 2-7) vs. 3% (95% CI 2-5), respectively. Conclusions: This systematic review underlines the low grade of accordance in reporting detailed data of bridging stents in F/B-EVAR. Renal TVs were more prone to complications, with an equivalent reintervention rate to visceral TVs. As to B-EVAR, the choice of B-EXP over S-EXP is still uncertain.