Structural failure in bridging stentgrafts for branched endovascular aneurysm repair: a case-control study

Abstract

Objective: To present a case series of spontaneous structural failure of bridging stentgrafts (BSGs) after branched endovascular aortic repair (bEVAR), as well as their failure types and their detection. While bEVAR is a safe and effective procedure, one main limitation is the reintervention rate associated with the BSGs. Structural failure of BSGs, defined as fabric disruption, stent fracture with leak or complete separation is a major cause for reinterventions and difficult to detect in computed tomography angiography (CTA).

Methods: From a multicenter bEVAR complication database, structural BSG failures were identified. Patient and BSG characteristics, detection mode, failure type, treatment and outcome were recorded and compared with bEVAR patients with intact BSGs.

Results: Twenty-three BSG failures were detected in 12 patients with only 43% directly identified in CTA, after a mean of 21.4 months after implantation. The BSGs were Advanta (n = 4), E-Ventus (n = 16) and BeGraft (n = 3) in 10 renal, 9 superior mesenteric, and 4 celiac branches. Religning with another BSG was successful in 20/22 cases, one BSG failure necessitated renal branch embolization (organ loss), and one mesenteric bypass surgery. Two reintervention-related mortalities occurred.

Conclusion: Structural failure of BSGs is a serious limitation for bEVAR, which can result in high reintervention rates and serious complications. BSG failure typically occurs in single-layer types and events are clustered in patients. The necessary reinterventions carry serious morbidity and mortality. Since the use as BSG in bEVAR is off-label with all current BSG manufacturers, caution is advised regarding patient-informed consent.

Keywords: Branched EVAR; Bridging stentgraft; Structural failure; Type 3 endoleak; bEVAR complication.

Fig. 1

Complete separation of right renal BSG with endoleak directly diagnosed at CTA (a), during angiography (b, c) and after successful religning (d)

Fig. 2

Membrane disruption of BSG in celiac trunk with visible endoleak in CTA (a) and angiography before (b) and after religning (c)

Fig. 3

Membrane disruption and wire fracture of BSG (failure mode 2) in celiac trunk with an endoleak surrounding the BSG in CTA (a, b) and angiography (c). Guide wire passage was possible through the fractured BSG into the aneurysm (d)

Fig. 4

An unspecific endoleak in CTA (a) was found to be a complete separation of the SMA BSG in angiography (c–e). Only after retrospectively calculated CT reformatations (b), the BSG fracture is visible. During catheterization, the dislocation of the distal fragment precluded endovascular repair

Fig. 5

Detection of an unspecified endoleak directly adjacent to the right renal BSG in arterial and venous CTA (a, b), confirmed to originate from a membrane disruption via angiography (c) and after successful religning (d)

Fig. 6

In the same procedure as in Fig. 1, the left renal BSG was unsuspicious in CTA (a), but an incidental membrane disruption was detected at angiography (b) and successfully treated (c)

Fig. 7

Endoleak adjacent to the left renal BSG in CTA (a, b). While the endoleak could not be confirmed in angiography (c), a previously undetected endoleak of the right renal BSG was found (d). Both BSGs were successfully religned. BSG = bridging stentgraft, CT = computed tomography, CTA = computed tomography angiography