In Vivo Preclinical Testing of a Bridging Stent for Fenestrated Endovascular Repair Using a Dedicated Swine Pararenal Aneurysm Model

Ann Vasc Surg. 2025 Jul 28;122:327-335. doi: 10.1016/j.avsg.2025.07.033. Online ahead of print.

ABSTRACT

BACKGROUND: To perform the preclinical evaluation of a new bridging stent for fenestrated endovascular aneurysm repair (FEVAR) in a dedicated animal model.

METHODS: A pararenal aneurysm was created in swines by suturing a bovine pericardium patch to the aorta, tailored to be compatible with available endografts. A cone beam computed tomography (CBCT) was performed to design custom-made fenestrated endograft. FEVARs were performed in hybrid room using retroperitoneal iliac accesses. Bridging stents were standard stents (BG, Begraft, Bentley) or new stents with a modified balloon to allow stent implantation and flaring in one step (BF, BeFlared, Bentley). Preoperative and postoperative CBCT were conducted to assess aneurysms anatomies and geometrical layout of the bridging stents.

RESULTS: Eleven pararenal aneurysms were created, all eligible for FEVAR. One animal died of aneurysm rupture at 64 days. Ten FEVARs were performed without complications after a mean delay from aneurysm creation of 90 days (range:43-119). Technical success was 90% (one type 1a endoleak). Ten BG and 10 BF were implanted successfully and showed comparable efficacy in all renal arteries which were all patent on completion angiogram; one type 1c endoleak in the BG group was observed and corrected by a redo inflation. No safety-related adverse events nor device malfunction were observed. The flaring dimensions and protrusion lengths were similar when comparing BF and BG.

CONCLUSION: A comprehensive evaluation of the safety and efficacy of a new bridging stent was possible by using the new pararenal aneurysm model to assess clinically relevant outcomes for FEVAR in real-life conditions.

PMID:40738451 | DOI:10.1016/j.avsg.2025.07.033