Efficacy and safety of embolization of brain arteriovenous malformations in pediatric patients: A systematic review and meta-analysis

Abstract

Background: Brain arteriovenous malformations (bAVMs) are rare vascular anomalies involving direct artery-to-vein connections that bypass capillaries. These high-flow lesions have a significant risk of rupture. Despite a prevalence below 10 per 100,000 and an average diagnosis age around 30 years, bAVMs cause notable morbidity, particularly in children.

Methods: Medline, Embase, and Cochrane were searched for English studies from January 2000 to February 2025. Our primary focus was on studies that included at least three pediatric patients with AVMs treated using embolization and that reported outcomes such as occlusion rates, complications, favorable clinical outcomes, and mortality. A meta-analysis of proportions with 95% confidence intervals was conducted under a random-effects model to pool the data. Baujat plots, leave-one-out, and meta-regressions sensitivity analyses were performed to address high heterogeneity.

Results: Our search encompassed 20 studies included. The analysis for immediate occlusion revealed a rate of 63 % (95 %CI: 28;92 %; I² = 92 %), and for long-term obliteration, 43 % (95 %CI: 23;65 %; I² = 88 %). Subanalysis based on the Spetzler scale demonstrated an 85 % long-term obliteration rate for patients classified as I to III, contrasting with 27 % for those classified as IV to V. Recurrence resulted in a pooled rate of 15 % (95 %CI: 0;45 %; I² = 85 %). Clinical outcomes were favorable, with a rate of 91 % (95 %CI: 79;98 %; I² = 59 %). Notably, 50 out of 263 patients experienced perioperative complications, yielding a rate of 15 % (95 %CI: 5;28 %; I² = 71 %). Among 50 perioperative complications, 29 were identified as hemorrhages, confirming a hemorrhage rate of 8 % (95 %CI: 1;19 %; I² = 68 %). No fatal events occurred among the 342 patients examined.

Conclusion: Our meta-analysis showed that embolization for pediatric bAVMs results in modest long-term obliteration rates and carries a significant risk of complications. Thus, while it may serve as part of a multimodal approach or as standalone therapy in selected cases, its effectiveness is limited and the risk of adverse events remains high.

Keywords: AVM; Arteriovenous malformation; Brain; Embolization; Pediatrics.