The FRESH Study: Treatment of Intracranial Aneurysms with the New FRED X Flow Diverter with Antithrombotic Surface Treatment Technology-First Multicenter Experience in 161 Patients

Abstract

Background and purpose: Flow diverters with antithrombotic coatings are increasingly used to improve the safety of flow diverter treatments of intracranial aneurysms. This study aimed to investigate the safety and short-term efficacy of the new FRED X flow diverter.

Materials and methods: Medical charts and procedural and imaging data of a consecutive series of patients with intracranial aneurysms who were treated with the FRED X at 9 international neurovascular centers were retrospectively analyzed.

Results: One hundred sixty-one patients (77.6% women; mean age, 55 years) with 184 aneurysms (11.2% acutely ruptured) were included in this study. Most aneurysms were located in the anterior circulation (77.0%), most frequently at the ICA (72.7%). The FRED X was successfully implanted in all procedures. Additional coiling was performed in 29.8%. In-stent balloon angioplasty was necessary in 2.5%. The rate of major adverse events was 3.1%. Thrombotic events occurred in 7 patients (4.3%) with 4 intra- and 4 postprocedural in-stent thromboses, respectively (1 patient had both peri- and postprocedural thrombosis). Of these thrombotic events, only 2 (1.2%) led to major adverse events (ischemic strokes). Postinterventional neurologic morbidity and mortality were observed in 1.9% and 1.2%, respectively. The rate of complete aneurysm occlusion after a mean follow-up of 7.0 months was 66.0%.

Conclusions: The new FRED X is a safe and feasible device for aneurysm treatment. In this retrospective multicenter study, the rate of thrombotic complications was low, and the short-term occlusion rates are satisfactory.

FIG 1.

Treatment of an incidental aneurysm of the ICA with the FRED X. The preinterventional angiography including 3D reconstructions (A–C) showed a saccular sidewall aneurysm of the right ICA in an asymptomatic patient. A FRED X FD was placed in the parent artery, covering the aneurysm neck (D–F). On the angiography 13 months after the treatment (G–I), the aneurysm was completely occluded.

FIG 2.

Treatment of an incidental PcomA aneurysm with the FRED X and coiling with intra- and postprocedural thrombosis. This patient, who had an incidental BA aneurysm treated with a Woven EndoBridge device (WEB; MicroVention) previously, presented with an incidental, irregularly shaped aneurysm of the ICA adjacent to the PcomA (A and B). After an uneventful treatment with FRED X implantation and coiling with a jailing technique (C), intraprocedural thrombus formation at the proximal part of the flow-diverting section of the stent was observed (white arrow in D). Tirofiban was instantly administered for 30 minutes, which led to a complete resolution of the thrombosis (E). Seven days after the treatment, after discontinuation of her ticagrelor medication, the patient presented with complete occlusion of the FD (F and G) with good collateralization via the contralateral side. Recanalization of the stent was achieved by tirofiban administration for 48 hours (H and I). The patient was neurologically asymptomatic the entire time.