The Enzen Trial: Analysis of EVAR Endoprosthesis Zenith and Endurant for Infrarenal Aortoiliac Aneurysms Regarding Outcomes, Endoleaks, and Reinterventions

Objective: The main objective of this paper is to analyze the outcomes regarding endoleaks, reinterventions, and death related to aneurysm complications in patients submitted to endovascular repair (EVAR) for abdominal aortoiliac aneurysm (AAA) using Endurant II (Medtronic) and Zenith Flex (Cook) endografts. Methods: This was a prospective, consecutive cohort study of patients with AAA who underwent EVAR between January 2019 and December 2022. Two groups of patients were evaluated: Group Endurant (patients submitted to EVAR with the use of Endurant II) and Group Zenith (patients submitted to EVAR with the use of Zenith Flex). Results: A total of 156 patients were evaluated. Group Zenith (67 patients, 42.9%) and Group Endurant (89 patients, 57.1%). The perioperative mortality was 5.1%, eight patients (six patients Group Zenith, and two patients Group Endurant, p=0.054). There were 28 patients (17.9%) submitted to urgent repair of the aneurysm (expansion or rupture), with no differences among the groups. There were 36 cases (23.1%) of later endoleak, with a higher incidence in Zenith group (23 patients, 34.3%) than Endurant group (13 patients, 14.6%, p=0.002), most of them Type II endoleak (21 patients, 13.4%). There were 12 cases of Type I endoleak, also with a higher prevalence in Zenith group (13.4%) than Endurant group (3.4%, p=0.002). Moreover, regarding limb graft occlusion (LGO), there were nine patients (5.8%), with a higher prevalence in Zenith group (9%) than Endurant group (3.4%, p=0.045). The overall survival in a Kaplan–Meier at 720 days was 82.3% in the Zenith group and 89.1% in the Endurant group, with no statistical significance among the groups (p=0.09). The freedom from reintervention rates in a Kaplan–Meier at 720 days was 82.8% in the Zenith group and 93.2% in the Endurant group (p=0.001). Conclusion: In this present study, Zenith endograft had higher rates of endoleaks, aneurysms related mortality, LGO and reinterventions than patients submitted to Endurant II endografts. The linear regression analysis showed that the presence of endoleaks, type of endograft device (Zenith graft) and limb graft occlusion were related to higher reintervention rates. Clinical Impact In this present study, Zenith endograft had higher rates of endoleaks, aneurysms related mortality, limb graft occlusions and reinterventions than patients submitted to Endurant II endografts. The main impact and the innovation that this article provides is an opportunity to evaluate and choose the best endograft suitable for the patient with AAA during EVAR.