Meuli, L.Gavali, H.Budtz-Lilly, J.Khashram, M.Lattmann, T.Lopez-Espada, C.Møller, C.M.McMillan, N.Ribeiro, T.F.Venermo, M.Mani, K.2025-09-172025-09-172025European Journal of Vascular and Endovascular Surgery, 2025; 1-611078-58841532-2165https://hdl.handle.net/2440/147408Available online 8 Sept 2025. OnlinePublObjective: To examine trends in treatment strategies and perioperative outcomes for intact and ruptured complex abdominal aortic aneurysms (cAAA) across seven countries. Design: Multinational, registry-based observational study within the VASCUNET framework. Methods: This study used aggregated data from vascular registries in Australia, Denmark, Finland, New Zealand, Portugal, Sweden, and Switzerland. Patients treated with open repair (OR) and fenestrated (or branched) endovascular aortic repair (F/BEVAR) for intact and ruptured cAAA between 2018-2022 were included. The primary outcome was perioperative mortality (30-day or in-hospital). Weighted perioperative mortality rates with 95% confidence intervals (95%-CI) were calculated and variations in treatment practices and outcomes were assessed. Results: 3344 patients treated for intact cAAA, and 547 patients treated for ruptured cAAA were included. An overall increase in the use of F/BEVAR for intact cAAA was observed, rising from 50% in 2018 to 54% in 2022, with Denmark showing the largest rise, from 33% to 71%. The highest F/BEVAR rate was seen in Australia at 68%, the lowest in Switzerland at 25%. In contrast, OR was the predominant treatment for ruptured cAAA, accounting for 94% of all procedures without a clear trend. The overall perioperative mortality for intact cAAA decreased from 5.2% (95%-CI: 3.3-7.0%) in 2018 to 2.4% (1.3-3.5%) in 2022, though the trend was not statistically significant (p=.09). No time trend was observed in the perioperative mortality for ruptured cAAA, with an overall mortality rate of 35.6%. Complication rates, including myocardial infarction, acute kidney failure, and respiratory failure were more frequent in OR patients. Conclusion: While the use of F/BEVAR for elective cAAA repair has increased and mortality rates show a declining trend, the treatment of ruptured cAAA continues to rely predominantly on OR, with high perioperative mortality rates. These findings highlight the need for ongoing advancements in endovascular technologies for ruptured cAAA repairs.en© 2025 The Author(s). Published by Elsevier B.V. on behalf of European Society for Vascular Surgery.Aortic Aneurysm; Abdominal/surgery; Endovascular Procedures/mortality; complex Abdominal Aortic Aneurysm; Fenestrated Endovascular Aneurysm Repair; Branched Endovascular Aneurysm RepairJournal article10.1016/j.ejvs.2025.08.007859667McMillan, N. [0000-0003-0027-3095]