A212 Long-term follow-up after intracranial aneurysm treatment using dual-layer flow-diverting stent (FRED): Update of a single-center experience in Barcelona

<h3>Introduction</h3> Flow diverter intracranial aneurysm treatment with the Flow Redirection Endoluminal Device (FRED) have been widely used in clinical practice, but the value of long-term clinical and angiographic follow-up has not been rigorously evaluated. <h3>Aim of study</h3> To describe the long-term outcome after intracranial aneurysm treatment with dual-layer flow-diverting stent (FRED) to evaluate effectiveness of endovascular treatment and long-term complications. <h3>Method</h3> A retrospective analysis of a prospective observational registry that included patients who underwent angiographical and clinical follow-up for ≥ 5 years after intracranial aneurysm treatment using stent FRED between 2015 and 2019 at Therapeutic Neuroangiography Department J.J Merland in Barcelona. Aneurysm occlusion rates, recurrence rates, modified Rankin scale score shifts to baseline, and delayed complications were assessed. <h3>Results</h3> A total 173 patients with 208 aneurysms had long-term follow-up, efficacy was evaluated in 156 (84.32%) cases: 132 (84.6%) had OKM C-D occlusion, 101/109 (92.7%) within the first two years and increased to 202/208 (97.1%) later on. Independent predictors of occlusion were immediate OKM grade B-C-D (OR 4.01, 95% CI 1.51 to 10.62), single aneurysm (OR 3.29, 95% CI 1.05 to 10.32), and small size aneurysm (OR 4.74, 95% CI 1.57 to 14.30). After the two years threshold, there were 7 reported symptomatic non-serious adverse events and changes in stent morphology were 8 without clinical repercussions. <h3>Conclusion</h3> This long-term follow-up study demonstrates that the FRED device is safe and effective for the long-term treatment of intracranial aneurysms, resulting in a high occlusion rate and a low incidence of complications. <h3>Conflict of Interest</h3> No