Ready-to-fenestrate Stent Grafts in the Treatment of Juxtarenal Aortic Aneurysms: Proposal for an Off-the-shelf Device

Objective: A prototype ready-to-fenestrate stent graft (RFSG) was designed with a fixed scallop, and eight potential fenestrations allowing for variation in the position of each renal artery (RA) relative to the superior mesenteric artery (SMA). We aimed to determine the proportion of juxtarenal aneurysms treatable using this potentially 'off-the-shelf' device.

Methods: A total of 439 consecutive orders for custom-made devices were analysed, and positions for potential fenestrations in the RFSG were determined, based on the most frequent anatomical target vessel variations: a fixed SMA scallop 12 mm deep at 12:00, RA fenestrations at 9:15, 10:15 (target within the range 8:45-10:45), 2:15 and 3:15 (target within the range 1:45-3:45), each either 19 or 28 mm from the graft edge (GE); (within the range 15-32 mm), and 6 x 8 mm in diameter. Proximal diameters of 24, 26, 28, 30, 32 and 36 mm were chosen.

Results: Of the 439 plans, 372 standard juxtarenal (SJR) cases, defined by the inclusion of a scallop and 0, 1 or 2 small fenestrations (12%, 13% and 75% of the cases, respectively) were identified and used to test the applicability of the model. Mean CP (clock position) for right RA was 9:30, for the left RA 3:00, being a mean of 21 +/- 5 and 22 +/- 5 mm, respectively from the GE. RA CP was within the RFSG range in 86% (right) and 88% (left) of the cases, with 96% and 98%, respectively, within the allowable distance from the GE. A total of 81% of all SJR cases were potentially treatable using the RFSG model.

Conclusions: An RFSG device would allow for the treatment of the majority of juxtarenal aortic aneurysms, which currently require custom-made devices.