Fenestrated TREO^® low-profile endograft in hostile access vessels

Background: The Fenestrated TREO^® is a new custom-made device for fenestrated endovascular aortic repair (FEVAR). Its 19Fr low-profile delivery system may be effective for patients with low-calibre or hostile access vessels (AV), reducing trauma risk, improving limb perfusion during percutaneous procedures, and broadening FEVAR indications. This study evaluates short- and mid-term outcomes of the device and its viability in patients with hostile AV. Materials and methods: Only patients with hostile AV treated with the Fenestrated TREO^® between 2022 and 2025 at a tertiary-care university centre were included. The primary endpoint was technical success. Secondary endpoints included AV-related intraoperative procedures, short- and mid-term morbidity, mortality, reintervention rate, AV-related complications and reinterventions, and stability of target vessels (TV). A sub-analysis compared patients with AV calibre >6.3 mm (group A) and <6.3 mm (group B). Results: Twenty-eight patients were included: 18 in group A and 10 in group B. Technical success was 100%, with target vessel cannulation achieved in 99.1% (one failure). Additional intraoperative AV preparation/adjunctive procedures were required in eight patients (28.6%; 1 vs. 7, p < .001). No perioperative or late deaths occurred. AV reinterventions were required in four patients (14.3%; 2 vs. 2, p = .561). Major complications occurred in four patients (14.3%), and three of 4 AV reinterventions were observed in this subgroup. One major reintervention was necessary. Early TV instability occurred in two patients (7.1%; 1 vs. 1, p = .712). During a median follow-up of 13 months, no late deaths or reinterventions were observed. Conclusions: In patients with hostile AV, the Fenestrated TREO^® graft showed high technical success rates and favourable short-term outcomes, with acceptable complication rates and excellent TV stability, aligning with results of other well-established endografts. Its low-profile design may be advantageous in complex AV anatomies. Additional intraoperative AV-related procedures mainly occurred in cases of very narrow AV (group B), while postoperative AV-related complications and reinterventions were similar between groups.