Recurrence of Angiographically Cured AVMs: Influence of Age, Angioarchitecture, and Hemorrhagic Presentation and Implications for Follow-Up

BACKGROUND: Arteriovenous malformation (AVM) recurrence after complete surgical resection is a rare but significant clinical event. The underlying mechanisms and factors that predict recurrence remain incompletely defined. METHODS: We conducted a systematic review and meta-analysis in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. We included case series reporting on AVM recurrence following an angiographically documented complete resection. Data on initial clinical presentation, patients' demographics, AVM features, and patterns of recurrence were extracted and analyzed. RESULTS: We included 15 studies with a total of 1287 patients in our meta-analysis. The overall estimated recurrence rate was 5.4%. Hemorrhagic presentation appeared as a major predictor: in fact, 94% of recurrences occurred in patients with a prior rupture, corresponding to a 7.3% (95% CI, 0.049-0.098) recurrence rate within this high-risk subgroup. Ruptured AVMs were associated with 4-fold higher odds of recurrence compared with unruptured AVMs (odds ratio, 4.072 [95% CI, 1.492-11.113]). Younger age was also found to be a key factor, with pediatric patients accounting for 89% of all recurrences. Deep venous drainage was associated with a nearly 5-fold increased risk of recurrence (odds ratio, 4.96 [95% CI, 1.801-13.662]), while eloquent brain location was not found as a statistically significant predictor. The mean time to recurrence was 39.6 (95% CI, 27.80-51.41) months, while follow-ups varied among patients. CONCLUSIONS: Hemorrhagic presentation, younger age, and deep venous drainage demonstrated to be significant predictors of AVM recurrence after complete resection, whereas vascular aging appears protective. In older individuals, proangiogenic mediators (VEGF [vascular endothelial growth factor], HIF-1 [hypoxia-inducible factor-1] α, eNOS [endothelial nitric oxide synthase], and MMPs [matrix metalloproteinases]) are downregulated via aging-related pathways, limiting neovascularization and making recurrence biologically less likely. These findings underscore the need for prolonged, risk-adapted surveillance protocols, particularly for high-risk pediatric patients who present with hemorrhage.