Treatment Outcomes of Endovascular Embolization Only in Patients with Unruptured Brain Arteriovenous Malformations: A Subgroup Analysis of ARUBA (A Randomized Trial of Unruptured Brain Arteriovenous Malformations)

BACKGROUND AND PURPOSE: Endovascular embolization only has been advocated for treatment of brain arteriovenous malformations in recent trials. Our aim was to evaluate the results of embolization only in a cohort of patients who were enrolled in the A Randomized Trial of Unruptured Brain Arteriovenous Malformations (ARUBA) study at 39 clinical sites in 9 countries. MATERIALS AND METHODS: We analyzed the rates and severity of stroke and death in patients who underwent embolization only. Events were identified through in-person neurologic follow-up visits performed at 6-month intervals during the first 2 years and annually, with telephone contact every 6 months thereafter. All event-related data were reviewed by independent adjudicators. RESULTS: Among 30 patients who had embolization planned, 26 underwent embolization only. A total of 13 stroke events were reported in the follow-up period among 26 subjects (ischemic, hemorrhagic, or both in 4, 7, and 2 subjects, respectively). The adverse event occurred after the first embolization in 11 of 13 patients. One patient had a major motor deficit, and 2 patients developed major visual field deficits. One event was fatal. The modified Rankin Scale score was 0–2 at last follow-up in 11 of the 12 stroke survivors. Estimated stroke-free survival was 46% at 12 months. CONCLUSIONS: Although the rates of stroke and/or death were high in patients treated with embolization only in ARUBA, the rates of favorable outcomes following stroke were high during follow-up.