Endovascular aneurysm repair in abdominal aortic aneurysms with hyperangulated necks: A stitch in time saves nine

The paper by Chinsakcha et al. ¹ opens by stating that papers have suggested that the endovascular aneurysm repair (EVAR) is ‘safe and efficacious’ when treating patients with abdominal aortic aneurysms and hyperangulated necks (HANs). Closer examination indicates the same study^2,3 of 45 patients with a mean beta neck angulation of 81° achieving a 31° post-EVAR reduction. This may be the key issue here in maintaining freedom from type 1A endoleakage at a robust 49.5 months' follow-up, even though device application was outside the instructions for use (IFU). This is considering there is a large body of contrary historical and modern evidence suggesting that HANs are linked to proximal type 1 endoleakage and reintervention rates with complications of up to 70% when conventional devices are used in HAN conditions outside of IFU, ⁴ , ⁵ accepting that at that time the possible role of fixation adjuncts such as Heli-FX EndoAnchors (Medtronic, Santa Rosa, USA) would not have been considered.

This then raises several issues in the 54 patients with HANs. Firstly, despite indicating evidence relating to Endurant (Medtronic) devices only, the authors have used Zenith (Cook Aortic Interventions, Bloomington, USA) and Excluder (WL Gore & Associates, Flagstaff, USA; predating the latest version licensed in HANs) in almost 60% of cases, when there is no relevant evidence to support the use in such situations. Secondly, why was an open surgical repair option not considered? Thirdly, the authors use Palmaz stents as options to straighten out the beta angle, when in fact these are not recommended for elective infrarenal EVAR with challenging anatomy. ⁶ The presence of Palmaz XL stents (Cordis Corporation, a Johnson & Johnson company, FL, USA) could possibly hinder further interventions. Fourth, despite the mention of the potential applicability of Heli-FX EndoAnchors these were not used, particularly in the group of patients in the later years presented.

There is now midterm data beyond 18 months (and beyond 60 months in some cases therein) supporting the use of EndoAnchors when HAN aspects are encountered, with very low type 1A endoleak and migration rates. ⁷ Additionally, where the authors mention additional radiation doses, this is not the case when EndoAnchors are used, in our experience, and represents another advantage. ⁸ The key has been individualised case planning for EndoAnchor deployment, especially longitudinally along the outer curve rather than just the typical circumferential deployments; this achieves robust graft adherence to the aortic wall, an issue the authors highlight. The authors therefore may have walked into a trap of their own making here to some extent, given the evidence base, device choice and toolkit that exists; the high type 1A endoleak and migration rates encountered – and interventions to correct these – may well have been largely avoidable. However, one must also consider the chronology of the data especially when the time period presented is 2010–2013, and therefore the authors may have had no options for at least some of the earlier patients. This goes with the old saying “prepare and prevent, don’t repair and repent” (Anon).