The use of a novel short dilator tip on the distal bifurcated component during fenestrated aortic repair to avoid reno-visceral bridging stents

BACKGROUND: The aim of this study was to evaluate the feasibility and efficacy of a modified delivery system of the distal bifurcated FEVAR component where the dilator tip was shortened to prevent damage to the renovisceral bridging stents.

METHODS: All consecutive patients from a tertiary referral center that underwent a FEVAR with a custom delivery system of the distal bifurcated endograft with a short tip between November 2017 and July 2019 were retrospectively analyzed. Only patients with complete fluoroscopic loops of the insertion and deployment of the distal endograft were included. The primary study endpoint was the degree of crossing of the fenestration bridging stentgrafts, that was graded as 'not crossing', 'partial crossing' and 'complete crossing' relative to the lowermost placed fenestration. Secondary endpoints included fenestration related adverse events, secondary interventions, changes in renal function, aneurysm related mortality and overall mortality.

RESULTS: 23 patients were included (21 (91%) juxta-renal aneurysms, 2 TAAA type IV (9%)). The lowermost fenestration was crossed in 4 (17.3%), partially crossed in 9 (39.1%) and not crossed in 10 (43.4%) cases. Partial compression or inadequate flaring of a fenestration stentgraft was identified in the intraoperative cone beam CT in 6 (26.0%) patients and corrected perioperatively. Technical success was 100%. Median follow up was 34 (27 - 38) months with two non-aneurysm related deaths during this period. Four patients (17.3%) underwent a secondary intervention related to a fenestration bridging stentgraft.

CONCLUSIONS: The use of a custom short dilator introducer tip on the bifurcated device during FEVAR reduces the need to cross the fenestration bridging stentgrafts and may result in less fenestration related adverse events. However, the reno-visceral segment is still frequently crossed by the iliac extension which may lead to adverse events. This could likely be avoided by a similar adaptation on the iliac extension delivery system.