Mid- to Long-Term Outcomes of an Early Experience with Fenestrated Endovascular Aortic Repair for Pararenal Versus Juxtarenal and Infrarenal Aneurysms.

BACKGROUND

The Zenith Fenestrated (ZFEN) platform is commercially available in the United States for fenestrated endovascular aortic repair (FEVAR) in infrarenal abdominal aortic aneurysms (AAAs) with neck lengths of ≥4 mm. However, ZFEN has been used outside manufacturer instructions for the use of AAA with shorter necks or more proximal extents. Long-term data characterizing ZFEN results in these real-world applications are limited. We describe the mid- to long-term outcomes of our early experience using ZFEN for FEVAR in the pararenal segment.

METHODS

We reviewed all ZFEN repairs performed between April 2012 and April 2017 at an academic referral center. Cases done using modified grafts or for EVAR salvage were excluded. Results up to 8 years of follow-up using ZFEN were compared between FEVAR for pararenal AAA versus juxta/infrarenal AAA. Primary outcomes included freedom from reintervention and overall survival.

RESULTS

There were 90 cases included (26 pararenal, 64 juxta/infrarenal). At 8 years, estimated freedom from reintervention was 67.4% versus 57.6% (P = 0.93), while overall survival was 35.9% versus 42.3% (P = 0.46) in the pararenal and juxta/infrarenal groups, respectively. In the series overall, 25 patients (27.8%) required reintervention, with seven (26.9%) in the pararenal group versus 18 in the juxta/infrarenal group (28.1%). Reinterventions were most often performed for endoleaks.

CONCLUSION

Pararenal FEVAR using the ZFEN platform demonstrated no statistically significant differences in freedom from reintervention or overall survival compared to juxta/infrarenal FEVAR. However, the study is underpowered to prove true equivalence due to sample size and low event rates. Reintervention rates remain high, primarily due to endoleaks within the first 2-3 years. While few aneurysm-related deaths were observed, long-term outcomes remain uncertain due to substantial loss to follow-up. Consequently, late endoleaks, ruptures, and reinterventions may be underestimated. These data suggest that pararenal ZFEN outcomes do not statistically differ from juxta/infrarenal outcomes, though uncertainty remains, requiring ongoing long-term surveillance.