Peggy Nguyen, MD
Since the publication of the ARUBA trial1 suggesting higher rates of neurologic morbidity and mortality with interventional therapy versus medical therapy for unruptured AVMs, conservative management with monitoring and symptom alleviation alone has gained acceptance. However, the study has been criticized in the interim for its short follow-up period of 33 months, the heterogeneity of interventional therapy used, and the excessive hemorrhage rates in the intervention group. Taking into account these limitations, it is not clear whether certain types of interventions may be beneficial over other types, nor is it clear whether long-term prognosis was adequately measured.
The authors address some of these gaps by performing a retrospective, multicenter cohort analysis of ARUBA-eligible patients who received treatment with radiosurgery and define predictors of AVM radiosurgery outcomes in ARUBA-eligible patients. 509 patients were included from a total of seven institutions and underwent radiosurgical treatment with successful AVM obliteration in 75% of the study subjects. A combined post-radiosurgery morbidity and mortality rate of 8.8% was demonstrated. 23 (4.5%) suffered permanent neurologic morbidity and 22 patients (4.3%) died, albeit no deaths were associated directly with the radiosurgery procedure. 69.5% of subjects achieved a favorable outcome. Variables independently associated with favorable outcomes were a smaller AVM maximum diameter and non-eloquent AVM location.
The authors appropriately point out that the primary treatment goal in the management of AVMs is the elimination of hemorrhage risk. This study provides compelling data on the safety of radiosurgery, which is minimally invasive and addresses some of the critiques of ARUBA, including a longer follow up period of up to 10 years. However, what the study does not do (and is not designed to do) is to more definitively address whether radiosurgery would have better outcomes compared to medical treatment. This would need to be addressed in further prospective randomized trials.
1. Mohr, et al. Lancet 2014 (393): 614-621
