Significant aortic neck dilation occurs after repair of juxtarenal aneurysms with fenestrated endovascular aneurysm repair

Objective: Aortic neck dilation is a reported mode of failure and can be associated with aneurysm sac expansion after standard endovascular abdominal aortic aneurysm repair (EVAR). Fenestrated EVAR (FEVAR) of the juxtarenal segment increases the seal zone length and is often used to treat this disease progression. However, the frequency and risk factors for neck dilation after FEVAR is unknown. Methods: We evaluated 124 consecutive FEVARs performed under an investigational device exemption clinical trial for juxtarenal aneurysms (ClinicalTrials.gov identifier, NCT01538056). The aortic diameter at the level of the superior mesenteric artery (SMA; highest fenestration) and lowest renal artery (lowest fenestration) was assessed from computed tomography angiography preoperatively, at 30 days, and annually thereafter. A subgroup analysis was performed to assess aortic neck dilation by the graft type used, degree of oversizing, infrarenal neck length, effective seal zone length, and aortic diameter at the level of the lowest and highest fenestration. Multivariable analysis was then performed to evaluate for predictors of aortic neck dilation. Results: Of the 124 patients, 56 had complete anatomic detail and follow-up data available for >= 3 years. Those without preoperative or follow-up data available were excluded. The aortic diameter had increased significantly by 3 years at the level of both the SMA (2.4 mm; P < .01) and the lowest renal artery (3.2 mm; P < .01). When those with and without aortic dilation (>3 mm) were compared, only oversizing differed at the level of the SMA (14% vs 19%; P < .01). At the level of the lowest renal artery, the graft diameter differed (30 mm vs 28 mm; P = .02). However, after adjusted analysis, these differences were not significant. Finally, a subgroup analysis was performed to evaluate aortic dilation over time stratified by anatomic factors and should that aortic dilation occurred across differing aneurysm diameters, percentage of oversizing, graft types, and seal zone lengths. Conclusions: Aortic neck dilation in the visceral segment can occur after endovascular repair of juxtarenal aneurysms using FEVAR. Further research is warranted to determine how these changes might affect the long-term outcomes.