Interventions for treating brain arteriovenous malformations in adults

Abstract

Brain arteriovenous malformations (AVMs) are the single most common cause of intracerebral haemorrhage in young adults. Brain AVMs also cause seizure(s) and focal neurological deficits (in the absence of haemorrhage, migraine or an epileptic seizure); approximately one fifth are incidental discoveries. Various interventions are used in an attempt to eradicate brain AVMs: neurosurgical excision, stereotactic radiotherapy/'radiosurgery' (using gamma knife, linear accelerator, proton beam, or 'Cyber Knife'), endovascular embolisation (using glues, particles, fibres, coils, or balloons), and staged combinations of these interventions. This is an update of a Cochrane review first published in 2006. To assess the clinical effects of interventions to treat brain AVMs in adults (with the aim of either partial obliteration or total eradication), using data published in randomised controlled trials (RCTs). We searched the Cochrane Stroke Group Trials Register (last searched November 2009), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2009), MEDLINE (1966 to November 2009) and EMBASE (1980 to November 2009). We searched international registers of clinical trials, the contents pages of relevant journals, and bibliographies of relevant articles (November 2009). We also contacted manufacturers of interventional treatments for brain AVMs (March 2005). We sought randomised trials of any or all of the interventions for brain AVMs, compared against each other or against usual medical therapy, with relevant clinical outcome measures. Two authors independently applied the inclusion criteria and reviewed the relevant studies. One ongoing RCT fulfils the selection criteria for this review: A Randomized trial of Unruptured Brain Arteriovenous malformations (ARUBA, www.arubastudy.org), comparing interventional treatment versus medical management for brain AVMs that have never bled. We also found two RCTs which tested the equivalence of two embolic agents for the pre-operative embolisation of brain AVMs (one published, one unpublished), but none of the primary or secondary outcome measures in these trials met our desired criteria. We also excluded a third RCT which studied three different blood pressure lowering treatments to induce deliberate hypotension during surgical resection of brain AVMs because the intervention was not the focus of this review. There is no evidence from randomised trials with clear clinical outcomes comparing different interventional treatments for brain AVMs against each other or against usual medical therapy to guide the interventional treatment of brain AVMs in adults. One such trial (ARUBA) is ongoing.