Exclusion of complex aortic aneurysm with chimney endovascular aortic repair is applicable in a minority of patients treated with fenestrated endografts

OBJECTIVES: The Medtronic Endurant II stent graft has recently received Conformite Europeenne (CE) approval for the use in chimney endovascular aortic repair (ChEVAR) for the treatment for juxtarenal aortic aneurysms. The aim of this study was to assess the percentage of patients treated by fenestrated endovascular repair who would have been alternatively suitable for the treatment by the CE approved Medtronic ChEVAR. METHODS: Preoperative computed tomography scans of 100 patients who underwent fenestrated endovascular aortic repair (FEVAR) between April 2013 and February 2017 were retrospectively assessed for the applicability of the ChEVAR technique according to the Medtronic instructions for use. Eligibility criteria included an aortic neck diameter of 19-30 mm, a minimum infrarenal neck length of 2 mm, a total proximal sealing zone of at least 15 mm, thrombus in the aortic neck in <25% of the circumference, and maximum aortic angulations of 60 degrees in the infrarenal, 45 degrees in the suprarenal segment and <45 degrees above the superior mesenteric artery. RESULTS: According to CE-approved inclusion criteria, 19 individuals (19%) would have been eligible for ChEVAR. In 81 patients, at least 1 measure was found outside instructions for use: (i) excluding factor was detected in 26 patients, (ii) incongruous measures in 28 patients and in 27 patients, 3-5 measures were outside the instructions for use. The most frequently identified excluding factor was an insufficient infrarenal neck at <2mm length (n = 63; 63%). CONCLUSIONS: Patients with juxta- or pararenal aneurysm treated by FEVAR are in 19% of the cases alternatively suitable for the treatment by ChEVAR within CE-approved instructions for use. While ChEVAR is suitable in many emergency cases, FEVAR offers a broader applicability in an elective setting.