Arteriovenous malformation – cerebral

Alternative Names

AVM – cerebral

Definition of Arteriovenous malformation – cerebral

A cerebral arteriovenous malformation is an abnormal connection between the arteries and veins in the brain that usually forms before birth.

Causes, incidence, and risk factors

The cause of cerebral arteriovenous malformation (AVM) is unknown. The condition occurs when arteries in the brain connect directly to nearby veins without having the normal vessels (capillaries) between them.


In about half of patiens with AVMs, the first symptoms are those of a caused by bleeding into the brain.

Signs and tests

A complete physical examination and neurologic examination are needed, but they may be completely normal.


Finding the best treatment for an AVM that is found on an x-ray or other imaging tests but is not causing any symptoms can be difficult. Your doctor will discuss with you:

Expectations (prognosis)

About 10% of cases in which excess bleeding (hemorrhage) is the first symptom are deadly. Some patients may have permanent seizures and brain and nervous system (neurological) problems.


David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 11/4/2010

Arteries of the brain

ADAM Medical Encyclopedia

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