Long-term outcomes of endovascular embolization and stereotactic radiosurgery as the first-line treatment for ruptured arteriovenous malformations: a propensity score-matched analysis using nationwide multicenter prospective registry data

Background: This study aimed to evaluate and compare the risk-benefit profiles of endovascular embolization (EM) and stereotactic radiosurgery (SRS) as first-line therapeutic strategies for the management of ruptured arteriovenous malformations (AVMs). Materials and methods: We included patients with ruptured AVMs who underwent EM or SRS as the first-line treatments from a nationwide prospective multicenter registry (the MATCH study) in China. Propensity score matching was employed to balance baseline characteristics between the EM and SRS groups. The primary outcomes were long-term hemorrhagic stroke or death, while secondary outcomes included long-term obliteration rates and neurological status. Subgroup analyses and sensitivity analyses using alternative study designs were conducted to ensure the robustness and consistency of the findings. Result: Of 3909 consecutive AVMs in the registry from 2011.08 to 2021.12, 1067 patients were eligible. After matching, 640 AVMs remained for the final analysis. The mean follow-up duration was 5.27 years. In terms of primary outcomes, SRS was associated with a lower risk of hemorrhagic stroke or death (hazard ratio [HR] 0.36, 95% confidence interval [CI] 0.23 to 0.58). Regarding the secondary outcomes, SRS was observed to have a significant advantage in long-term obliteration (odds ratio [OR] 7.89, 95% CI 5.15 to 12.11), and the incidence was significantly lower in the SRS group than in the EM group for the disabling neurological deficits (OR, 0.42, 95% CI, 0.25 to 0.70). Results of subgroup analyses and sensitivity analyses were consistent in the trend but with slightly varied powers. Conclusion: This study suggests that SRS can be more effective than EM in preventing future hemorrhagic stroke or death, achieving complete obliteration, and reducing long-term neurological disability.