Hemorrhage risk after partial endovascular NBCA and ONYX embolization for brain arteriovenous malformation

Abstract

Objective: To estimate for hemorrhage risk of partially endovascularly embolized brain arteriovenous malformation (BAVM).Methods: We retrospectively reviewed 147 consecutive patients with BAVM-treated mainly with endovascular N-butyl cyanoacrylate (NBCA) and ONYX embolization. In Kaplan–Meier survival analysis, the index date was the dated of initial endovascular embolization; cases were censored at time of subsequent intracranial hemorrhage (ICH), or loss to follow-up, and multivariate proportional-hazards regression models included age of presentation (⩽30 years old), clinical presentations, and other potential confounders.Results: We reviewed 147 patients with BAVM (58·8% male; mean age±SD at treatment: 27·5±11·1 years) treated with endovascular embolization. One hundred and forty-four NBCA and 76 ONYX embolizations were performed. Complete obliteration of BAVMs was achieved in 29 patients (19·7%). Thirty-two (21·8%) patients were treated with additional Gamma-knife radiosurgery. During 499·5 years of follow-up, 15 partially treated patients suffered a further hemorrhage, which caused four deaths. The crude annual risk of hemorrhage was 3·0% and the annual death rate was 0·8%. Among partially treated patients with hemorrhage at initial presentation, the risk of hemorrhage was 3·8%, while the risk of hemorrhage for patients without hemorrhage at initial presentation was 2·5%. The annual rate of subsequent hemorrhage was 2·6% for non-ICH and 4·2% for ICH in the partial NBCA embolization group compared with 2·4% for non-ICH and 2·4% for ICH in the partial ONYX embolization group.Conclusions: The effect of partial AVM embolization with liquid embolic agents may still be unclear as for risk reduction of annual hemorrhage rate of cerebral AVM.