Commentary on tightrope technique for facilitating complex endovascular aortic repair

Complex endovascular aneurysm repair using branched and fenestrated grafts, custom manufactured or physician modified, can be a life-saving procedure in those unsuitable for alternative open or endovascular repair. Challenges arise commonly during these cases, necessitating flexibility and innovation for successful management. A frequent hurdle, ie tortuosity of the aortoiliac segments, is presented in a case report by Spinosa and Adams,¹ wherein the authors describe a novel approach to managing intraoperative device migration using endoforceps.

Considerations for navigating the anatomically hostile aorta, and the acceptable aortoiliac anatomy for endovascular repair, are contextualized by elective versus emergent presentations. The large symptomatic aneurysm in an unfit elderly patient, and concomitant tortuous paravisceral aortic anatomy described by Spinosa and Adams, forces an acceptance of aortic anatomy that might otherwise be unsuitable for endovascular therapying in the elective setting. The authors describe the sequential use of an occlusion balloon, followed by a novel endograsp tightrope technique of the fenestrated component to stabilize it during advancement of the distal bifurcated device. Although the use of a compliant balloon for endograft stabilization has previously been described, other techniques, notably establishment of through-and-through access, have been more widely adopted to negotiate the tortuous aorta.² The authors argue that transaxillary/brachial flossing presents additional risks related to access and embolization. Although all vascular access presents a potential site of complication, the rates associated with through-and-through strategies are low overall,^3,4 cerebral embolization is moderately increased by flossing for thoracic endovascular aneurysm repair, in contrast with the proportionally three- to four-fold greater predictors of cerebral embolization, such as intraoperative blood loss or thrombus-laden aorta.⁵ More recent experience with transfemoral-only approach for branched/fenestrated endograft implantation has been favorable, compared with combined upper and lower extremity access.6, 7, 8, 9 The novelty of the reported tightrope technique precludes an appreciation of its potential intraoperative and perioperative complication rates. The use of the tightrope technique might, therefore, be best valued as an adjunct after the sequential application of other endograft aortic-stabilizing maneuvers.

In considering tightrope technique use outside of the emergent arena, several issues arise. One, that aortic tortuosity of this extent, falls predictably outside of the indications for endovascular devices because intraoperative device failure, malrotation, and visceral malalignment are predictable consequences of implantation in this circumstance. Second, that the purpose of any aneurysm repair is the durable exclusion of an aortic aneurysm. In the case report, although the patient’s 30-day computed tomography angiography scan demonstrates satisfactory aneurysm exclusion, the test of an endograft under these rotational and compressive forces is long-term durability. We know that visceral branch instability in fenestrated and branched endografts is most common in the first 18 months postoperatively.¹⁰ Unfortunately, the patient in this case report survived less than 1 year postoperatively, so the long-term consequences of any target vessel instability caused by endoforceps manipulation of the fenestrated endograft cannot be fully appreciated. Of more concern, the deformational forces of the highly tortuous native aorta on a complex endograft over time are incompletely understood. This outcome ultimately raises the issue of the appropriateness of aortic repair in groups of patients with a high comorbid burden and hostile aortioiliac anatomy.

The opinions or views expressed in this commentary are those of the author and do not necessarily reflect the opinions or recommendations of the Journal of Vascular Surgery or the Society for Vascular Surgery.