Background Ruptured brain arteriovenous malformations (bAVMs) are at increased risk of re-hemorrhage but management has historically been conservative. This is because: (1) ruptured bAVMs have not been considered as catastrophic as ruptured cerebral aneurysms, (2) surgical resection is aided by waiting for brain edema to resolve and clot to liquefy and (3) fear exists that partially treated bAVMs may be more dangerous than those untreated. The purpose of this study was to determine the feasibility and safety of acute embolization in patients with ruptured bAVMs.

Methods 21 consecutive patients who underwent acute embolization of ruptured bAVMs from 2007 to 2011 were retrospectively reviewed. All treatments consisted of embolization exclusively using Onyx liquid embolic agent. Neurological outcomes were assessed using the Glasgow Outcome Scale (GOS) at hospital discharge following initial treatment.

Results Nine patients (43%) were male, mean age was 38 years (range 8–75) and initial embolization was performed at a median of 4 days after ictus (mean 5.8, range 0–19). Spetzler–Martin grades ranged from I to VI (mean 3, median 3). In seven patients (33%) the AVM was completely occluded with a single treatment. With subsequent embolizations, complete occlusion occurred in four additional patients (19%). Six patients (29%) had post-embolization AVM resection and one patient (5%) had post-embolization gamma knife irradiation. None has suffered subsequent hemorrhages (mean follow-up 7.5 months). The mean discharge GOS of all patients was 4.4 (range 1–5).

Conclusion Treatment of ruptured bAVMs is often delayed but our experience with Onyx suggests that acute embolization is safe and feasible.