Conservative, Endovascular, and Open Repair Treatment for Proximal Bare Metal Stent-Strut Separation and Consecutive Dysfunction of the Suprarenal Fixation and Dislocation of the EVAR Stent-Graft Prosthesis
Mikolaj Walensi, Varsha Prakash Rayakar, Jonas Hensel, Susanne B. Kiewitz, Nikolaos Tsilimparis, Kai Nassenstein, Christian Mikat, Michal Piotrowski, Johannes N. HoffmannBackground:
Endovascular aortic repair (EVAR) has been the standard treatment for abdominal aortic aneurysms (AAAs) for about 20 years, offering advantages in morbidity and mortality in the short- and mid-term. However, long-term complications, such as endoleaks (ELs) and aneurysm sac rupture, can arise due to mechanical issues with the EVAR technique, including material fatigue.
Patients and Methods:
We report the cases of 3 patients with partial or total separation of the bare metal suprarenal stent-struts separation in the bifurcated Medtronic Endurant II EVAR stent-graft, treated with various methods. Here, the BMS-SSS occurred 2.5, 6.8, and 6.7 years, respectively, after the initial EVAR procedure. All 3 patients were treated using different (conservative, endovascular, and open surgical) therapy methods.
Discussion:
Since the introduction of the EVAR technique, advancements in prosthesis design have significantly reduced complications resulting from different types of ELs. Bare metal suprarenal stent-strut separation (BMS-SSS) remains as a rare issue, being associated with EL type I, graft migration and late aneurysm sac growth and rupture. Treatment options include conservative management for stable cases, endovascular interventions like stent realignment or cuff implantation, and, as a last resort, open surgery with late open conversion. Strict surveillance after EVAR is essential to detect BMS-SSS in time and to prevent serious, potentially-life-threatening complications.
Clinical Impact
This study highlights the critical necessity of lifelong, strict surveillance after EVAR to detect rare but life-threatening mechanical failures like bare metal suprarenal stent-strut separation (BMS-SSS). It provides a comparative clinical insight into managing this specific complication using conservative, endovascular, and open surgery approaches. For clinicians, these findings mean that treatment must be highly individualized based on anatomical conditions, graft condition and patient stability, rather than relying on a standardized protocol. Ultimately, this shifts clinical practice toward heightened vigilance regarding long-term material fatigue and expands the decision-making framework for late EVAR complications.