FRED X flow diversion stenting for unruptured intracranial aneurysms: US multicenter post-market study.

Background: The Flow Re-direction Endoluminal Device (FRED) X is a next generation flow-diverting stent for treating intracranial aneurysms. Its surface modification (X technology) aims to minimize device thrombogenicity. Early post-market multicenter data from the US are lacking.

Methods: We conducted a retrospective multicenter analysis of consecutive FRED X procedures performed to treat unruptured intracranial aneurysms at four US centers (March 2022 to January 2024). Cases with ruptured aneurysms or extracranial aneurysm location were excluded (n=10). We assessed patient and aneurysm characteristics, antithrombotic management, safety events, and both clinical and angiographic (effectiveness) outcomes.

Results: In this cohort, 101 patients underwent FRED X stenting for 117 aneurysms. Most aneurysms were saccular in shape (95.7%) and located at the C6-C7 segments of the internal carotid artery (72.6%). Thromboembolic events occurred in 5.9% of the cases, leading to one instance of permanent procedure related morbidity (1.0%). No procedure related mortality (0%) was observed. Device related issues were recorded in 2.0% of cases. At the 6 month follow-up, complete aneurysm occlusion was achieved in 58% of aneurysms. At the last available follow-up (6-12 months), 74.8% of aneurysms were adequately occluded.

Conclusions: FRED X stenting for unruptured intracranial aneurysms demonstrated low rates of neurological morbidity and periprocedural complications. Early aneurysm occlusion rates were appropriate, but further mid-term and long term follow-up is required. These findings support the early safety and effectiveness of the FRED X device for intracranial aneurysm treatment.