Abstract WP21: Cognitive Improvement In Patients With Dural Arterio-venous Fistula After Endovascular Embolization: Interim Analysis Of The NAIF Study

Abstract

Introduction: Dural arteriovenous fistulae (dAVF) are rare acquired intracranial vascular malformations with clinical manifestations varying from asymptomatic lesions, non-hemorrhagic neurological disorders, and intracranial hemorrhage which may be fatal. In addition, patients with dAVF often have cognitive impairments. This study assessed whether endovascular embolization improves cognitive performance in patients with dAVF. Methods: NAIF was a prospective study including all the patients with a clinical diagnosis of dAVF (excluding those with acute intracranial hemorrhage secondary to venous hypertension) who underwent successful embolization at 5 hospitals in Spain between January 4, 2018 and January 7, 2020. Patients were categorized by risk of hemorrhage (Cognard classification 1-2A and 2B-4) via angiography. A neuropsychological evaluation covering 5 domains of cognitive function (memory, attention and executive functions, language, praxis, gnosis) was completed at baseline and a 3-month follow-up. Paired sample t-tests were used to compare mean Z-scores for cognitive tests pre- and post-treatment, where higher Z-scores signify better cognitive status. Results: A preliminary group of 15 patients (mean age 60, [range 23-83 years], 4 [26.7%] female) were included. Six patients presented with low hemorrhagic risk (Cognard1-2A) and 9 with high hemorrhagic risk (Cognard 2B-4). In the post-treatment neuropsychological evaluation, patients exhibited improved performance in executive function in the Semantic and Phonetic Fluency test (-0.57 vs. 0.21; p=0.01) and increased performance in Verbal Memory Learning (-1.45 vs. -0.82; p=0.014) relative to baseline. The remaining cognitive evaluations did not show significant differences, although there was a trend of language improvement in the Boston naming test (0.95 vs. 1.12; p=0.093). Improvements were observed in both high- and low-risk patients, and no patients experienced cognitive worsening after the intervention. Conclusion: This study suggests that endovascular embolization imparts cognitive benefits for dAVF patients undergoing endovascular embolization, and may be beneficial even for patients with a low risk of hemorrhage.