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Birthmarks and Vascular Anomalies Center
BVAC Physicians and Staff
Information About Vascular Anomalies
Treatments/ Philosophy
Resources for Patients

Birthmarks and Vascular Anomalies Center
Arteriovenous Malformations (AVMs)

An AVM is an abnormal collection of blood vessels in which normal capillaries are absent allowing direct communication between arteries and veins. These are termed "high flow" vascular malformations because of the rapid shunting of blood through the lesion. AVMs are evident at birth in only 40% of patients. They may appear and/or progress during childhood, puberty, pregnancy, and throughout adult life. They can also be caused by trauma.

The progression of AVMs has been classified into 4 stages:

  • Stage 1 - Dormancy
    • AVMs may look like a reddish area on the skin or a pulsing mass under normal skin.
  • Stage 2 - Expansion
    • The affected red or pulsatile area gets bigger and becomes warm, tender and may have pulsations and enlarged surface veins.
  • Stage 3 - Destruction
    • Ulcers and bleeding develop.
  • Stage 4 - Destruction plus Congestive Heart Failure
    • So much blood is going through the AVM that it affects the heart.

Arteriovenous Malformation of the Ear

Diagnosis of an AVM involves a careful physical exam, ultrasound/Doppler studies, MRI/MRA, and if necessary, cardiac evaluation.

Angiogram of Right Foot AVM

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Treatment may include embolization and surgical removal although extreme care must be taken because some treatments can cause the AVM to worsen or expand.


Updated: November 30, 2007
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