Association of Nidus Size and Rupture in Brain Arteriovenous Malformations: Insight from Angioarchitecture and Hemodynamics

Abstract

Abstract Objective: This study aims to investigate the correlation between AVM size and rupture by examining natural history, angioarchitecture characteristics, and quantitative hemodynamics. Methods: A retrospective review of 90 consecutive AVMs from the MATCH registry was conducted. Patients were categorized into small nidus (<3cm) and large nidus (≥3cm) groups based on the Spetzler-Martin grading system. Natural history analysis used prospective cohort survival data, while imaging analysis examined angioarchitecture characteristics and quantitative hemodynamic parameters measured with QDSA. Results: The small-nidus group had a significantly higher annualized rupture risk (2.3% vs. 1.0%; p = 0.011). Cross-sectional imaging revealed independent hemorrhagic risk factors, including small nidus (OR, 4.801; 95%CI, 1.280–18.008; p = 0.020) and draining vein stenosis (OR, 6.773; 95%CI, 1.179–38.911; p = 0.032). Hemodynamic analysis identified higher stasis index in the feeding artery (OR, 2.442; 95%CI, 1.074–5.550; p = 0.033), higher stasis index in the draining vein (OR, 11.812; 95%CI, 1.907–73.170; p = 0.008), and lower outflow gradient in the draining vein (OR, 1.658; 95%CI, 1.068–2.574; p = 0.024) as independent predictors of AVM rupture. The small nidus group also showed a higher likelihood of being associated with hemorrhagic risk factors. Conclusion: Small AVM nidus has a higher risk of rupture based on natural history, angioarchitecture, and hemodynamics Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT04572568