Detection of a Rare Complication of Endovascular Treatment for Brain Arteriovenous Malformation with Echocardiography.

A brain arteriovenous malformation (AVM) is a congenital malformation of the vascular system, in which an abnormal short circuit (vascular malformation) connects cerebral arteries and veins. When the brain AVMs are diagnosed, the majority of them must be closed with surgical or endovascular treatment, because only a small portion of the brain AVMs remain asymptomatic during the patient's life. Endovascular transarterial embolization using Onyx Liquid Embolic System is a suitable method for treating brain AVMs. Previously known complications of Onyx usage are bleeding and neurologic deficits. We report a young man with a rare complication of Onyx injection, clinically silent distal embolization to the heart chamber and pulmonary circulation, discovered incidentally with echocardiography.