Long-term results of endovascular aortic arch replacement: European multicenter experience with the Nexus aortic arch graft system

OBJECTIVES: Total microinvasive endovascular treatment with branched stent grafts is showing promising results as an alternative therapeutic option for high-surgical-risk patients with aortic arch pathologies. The aim of our retrospective European multicenter study is to evaluate the performance and safety of the NEXUS™ Aortic Arch Stent Graft System (bi-modular, off-the-shelf aortic arch stent graft system), in both its single- and double-branch configurations, in this patient population. METHODS: The study includes patients treated with the NEXUS Aortic Arch Stent Graft System and NEXUS DUO Aortic Arch Stent Graft System, in 6 centers in Europe. Anatomical inclusion criteria included adequate landing zone in the ascending aorta, brachiocephalic trunk, and descending thoracic aorta. Preparatory debranching procedure was performed in all patients. The primary end point was rate mortality at 30-days and overall survival at follow up. The secondary end points included the incidence of procedure-related unplanned intervention, stroke, paraplegia and endoleak at 30-days and at follow-up. Clinical and radiologic follow-up was performed at each study site at 30 days, 6 months and on a yearly basis thereafter up to 7 years postoperatively. RESULTS: A total of 34 patients were treated from December 2016 until July 2024, 74% males, with a mean age of 73 [IQR 64-76] years were treated with 100% procedural success. The primary pathology treated was residual chronic dissection 17 (50%) patients, followed by aortic arch aneurysm, observed in 12 (35%) patients. A total of 25 (75%) patients had previously undergone open aortic surgery; in particular, 23 (67.6%) had an ascending aorta replacement. The mean EuroSCORE II value was 5% [IQR 4-11]. NEXUS with a single branch, NEXUS DUO, and Nexus with a single branch and in-situ fenestration were used in 19 (56%), 11(32%), and 4 (12%) patients, respectively. In most cases, the main module branch was deployed in the brachiocephalic trunk (29 patients, 85.3%) and the second branch in the left subclavian artery (12 patients, 35%). The 30 days mortality rate was 5.9%, including one death attributed to the device and one due to procedural complications. Overall survival at 1, 3, and 7 years was 81%. Three device or procedure-related unplanned reinterventions were recorded within the first 30 days post-implantation, and the cumulative incidence of this reinterventions was 9.3% at 6 months and 14% at 1 year. The 30-day any-stroke rate was 14.7% (only one major stroke), with no new cerebrovascular events at follow-up. The endoleak rate at 30 days and one year was 5.9% and 9.4%, respectively, no endoleaks were reported in the follow-up beyond one year. No paraplegia was reported. CONCLUSIONS: In conclusion, our data confirm good results regarding the safety and efficacy of the single- and double-branch NEXUS system for the treatment of aortic arch pathologies in high-surgical-risk patients, particularly those who have previously undergone cardiac surgery.