Summary: Background: The objective of the study was to analyze mid-term results of unselected patients treated with the TREO (Terumo Aortic, Florida, USA) device at six German hospital sites. Methods: A multicenter, retrospective analysis of patients treated within and outside instructions for use (IFU) from January 2017 to November 2020 was performed. Primary outcomes were technical success, mortality and endograft related complications according to IFU status. Secondary outcomes were aneurysm/procedure related re-interventions. Results: 150 patients (92% male, mean age 73 ±8 years) were treated (within IFU 84% vs. outside IFU 16%) with the TREO device for abdominal aortic aneurysms (n=127 intact, n=17 symptomatic and n=6 ruptured; p=0.30). Technical success was achieved in 147/150 (within IFU 99% vs. outside IFU 92%, p=0.08). 30-day mortality was 2%, one year and overall mortality was 3% and 5%. During a mean follow-up of 28.4 months (range: 1–67.4 months), 35 (25%; within IFU 23% vs. outside IFU 35%, p=0.23) patients suffered from endoleaks. The majority were endoleaks type II (n=33), the remaining type Ia (n=5) and type Ib (n=3). No endoleaks type III-V, migrations or aneurysm ruptures occurred. Overall, 19 patients (13%; within IFU 13% vs. 15% outside IFU, p=0.70) received a secondary intervention: nine endoleak related endovascular procedures, three open conversions, two endograft limb related interventions, four surgical revisions of the femoral access sites and two bowl ischemia related procedures, respectively. Conclusions: This non industry-sponsored, multicenter trial indicates that using the TREO device in a real-world setting (both within and outside IFU) seems feasible in the treatment of patients suffering from AAA. While the rate of complications and secondary interventions is in line with previously published data, the findings highlight the fact that standard EVAR is associated with serious adverse events.