Brain AVMs are relatively rare, though their potential for ICH along with the existence of effective treatments makes their diagnosis and management essential to the community. The 2-4% annual incidence of such secondary ICH creates controversy regarding treatment for asymptomatic patients. Brain AVMs thus require multidisciplinary evaluation for optimal management especially for surgical grades III - V lesions that often require some combination of embolization, microsurgery, and/or radiosurgical treatment. Currently there is no designated medical therapy for bAVM, though there is growing animal and human evidence supporting a role for bevacizumab to reduce the size of AVMs in the brain and liver, respectively. This proposal is a pilot study to assess the efficacy and safety of bevacizumab in humans with bAVMs.