Toward an “Off-the-Shelf” Fenestrated Endograft for Management of Short-Necked Abdominal Aortic Aneurysms: An Analysis of Current Graft Morphological Diversity

Purpose: To examine the feasibility of an ‘‘off-the-shelf’’ fenestrated endograft repositoryto broaden the applicability of fenestrated endovascular aneurysm repair (f-EVAR) to agreater number of emergent cases.Methods: Graft dimensions of 438 consecutive customized fenestrated endografts forjuxtarenal aneurysms were obtained from the commercial manufacturer, classified intotolerance ranges, and encoded in a database for statistical analysis. Limits of variability fortolerance ranges were set to maintain target vessel patency within acceptable surgicallimits at deployment. Key independent structural variables were identified and analyzed fortrends. Detailed analysis was performed of 282 (64%) 3-fenestration endografts,representing 232 structurally unique grafts.Results: Seven key individual structural variables were identified, constituting 21,952possible combinations. Only 8/232 (3.5%) graft configurations were compatible with $3patients. Nearly a third of the patients (86/282, 30.5%) were treated by a range of 36customized endografts. Graft dimensions were not uniformly distributed; there weremodal sizes that were likely to recur at a median 39 cases (95% CI 17–121). Deployingendografts incorporating double diameter-reducing tie technology increased the tolerancesuch that 28 grafts would treat 81% of this population.Conclusion: The current design of fenestrated stent-grafts means that an ‘‘off-the-shelf’’option is not practicable. However, there is evidence of recurrent patterns of morphology.Statistical modeling is capable of predicting demand for graft configurations. Innovationsin f-EVAR endograft technology may decrease the required variability in graft morphology,paving the way for ready-to-deploy fenestrated stent-grafts.J Endovasc Ther. 2010;17:78–85Key words: Abdominal aortic aneurysm, stent-graft, endovascular aneurysm repair,fenestrated stent-graft, stent-graft configuration