Editors' commentary

Abstract

Drs Haulon and Lee have provided an extensive and broad comparison of two endovascular approaches to juxtarenal, pararenal, and thoracoabdominal aortic aneurysms, namely fenestrated/branched endovascular repairs (fen-EVAR) or snorkel/chimney (ch-EVAR) repairs. Both are respected experts and leaders in the area of endovascular repair of complex aortic aneurysms and have advocated strongly for the responsible reporting and evaluation of the results of fen-EVAR and ch-EVAR. Although there has been no randomized trial, nor is one likely needed or possible, several meta-analyses have been performed to attempt a comparison between these approaches. Dr Haulon highlights the difficulties in comparing these approaches, as the patients and their anatomies preclude any meaningful and direct comparison. As both discussants report, single-center ch-EVAR experiences tend to report higher mortality rates and rates of type I endoleaks and poorer target vessel patency than fen-EVAR reports. However, these differences lessen when emergency cases are excluded, which are treated in higher proportion in ch-EVAR series, and technical features are considered. Both approaches have benefitted from the expertise of our discussants, as Dr Haulon has optimized the fenestrated/branched approach and helps to lead the transition from solely custom-made devices to the more readily available off-the-shelf components. Dr Lee provides important technical observations regarding the ch-EVAR technique regarding the direct relationship with number of parallel stents and risk of type I endoleak (so-called “gutter” endoleaks due to incomplete conformability of main body and parallel stents) and the inverse relationship between length of overlap and target vessel patency. As expertise in both techniques has developed, the differences in outcomes and results have become less apparent. This is evident in the recently published multicenter, international PERformance of the chimney technique for the treatment of Complex aortic pathoLogiES Registry (PERICLES) by Dr Donas and colleagues.1Donas K.P. Lee J.T. Lachat M. Torsello G. Veith F.J. PERICLES investigatorsCollected world experience about the performance of the snorkel/chimney endovascular technique in the treatment of complex aortic pathologies: the PERICLES registry.Ann Surg. 2015; 262: 546-553Crossref PubMed Scopus (220) Google Scholar This registry reported on 517 patients treated in U.S. and European centers over a 6-year period with a mean follow up of 17.1 months. The results were commendable but of particular interest was the variability in devices used. Different main bodies of commercially available transrenally fixated endografts were preferred by various centers and different parallel stents were also used. The uncertainty regarding the optimum devices is not unique to ch-EVAR. Such issues as the use of fenestrations and/or directional side branches and which is the best bridging stent are issues with fen-EVAR that have yet to be fully elucidated. As procedure- or pathology-specific devices continue to be developed, the results of both approaches should continue to improve. Our debaters have eloquently outlined the strengths and weaknesses of both approaches at the present time. However, as fenestrated/branched endografts become more available, especially off-the-shelf versions, fen-EVAR will likely be the preferred endovascular approach to complex and extensive aneurysm therapy in centers that provide such care. ch-EVAR will not disappear, however, and will continue to be an important alternative in specific bail-out situations, emergency settings, and in cases of adverse aortic or iliac anatomy. Surgeons are also encouraged to report their results with these technologies, both good and bad, so we can better understand their role in treating these complex patients.2Mastracci T. Scientific methods and the reporting of negative results: critically important to patient safety [published online ahead of print September 21, 2015] Eur J Vasc Endovasc Surg doi: 10.1016/j.ejvs.2015.08.007Google Scholar Debate: Whether branched/fenestrated endovascular aneurysm repair procedures are better than snorkels, chimneys, or periscopes in the treatment of most thoracoabdominal and juxtarenal aneurysmsJournal of Vascular SurgeryVol. 62Issue 5PreviewVascular surgeons are an innovative group, and during the last decade, we have seen unparalleled advances in the endovascular treatment of extensive aortic pathologies. Collaborative efforts between surgeons and industry have introduced fenestrated and branched devices that are becoming more widely used, with wider regulatory approval, availability, and less need for customization. Prior to this, parallel stent approaches had been developed to fill the void where this technology was not available or for urgent cases. Full-Text PDF Open Archive