Arteriovenous malformation

Abnormal connection between arteries and veins

An arteriovenous malformation (AVM) is an abnormal connection between arteries and veins, bypassing the capillary system. This vascular anomaly is typically congenital, meaning it is present at birth, but it can also develop later in life. AVMs can occur in various parts of the body, including the brain, spine, lungs, and skin.

Pathophysiology

AVMs are characterized by a complex, tangled web of arteries and veins. Normally, arteries carry oxygen-rich blood from the heart to the body, and veins return oxygen-depleted blood back to the heart. In an AVM, the direct connection between arteries and veins disrupts this process, leading to potential complications such as bleeding or reduced oxygen delivery to tissues.

Symptoms

The symptoms of an AVM depend on its location. In the brain, AVMs can cause headaches, seizures, or neurological deficits. Spinal AVMs may lead to back pain, weakness, or paralysis. Pulmonary AVMs can result in shortness of breath or cyanosis. Cutaneous AVMs may appear as red or purple lesions on the skin.

Diagnosis

AVMs are often diagnosed using imaging techniques such as magnetic resonance imaging (MRI), computed tomography (CT) scans, or angiography. These methods help visualize the abnormal blood vessels and assess the risk of complications.

Treatment

Treatment options for AVMs vary based on their size, location, and symptoms. They may include:

• Surgical resection: Removing the AVM through surgery.
• Endovascular embolization: Injecting materials to block the abnormal vessels.
• Stereotactic radiosurgery: Using focused radiation to shrink the AVM.

Prognosis

The prognosis for individuals with an AVM depends on several factors, including the AVM's size, location, and whether it has bled. Untreated AVMs in the brain have a risk of bleeding, which can lead to serious complications or death.

Related pages

• Cerebral arteriovenous malformation
• Vascular malformation
• Capillary malformation
• Venous malformation

Arteriovenous_malformation

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  Arteriovenous malformation in the brain, low magnification
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  Arteriovenous malformation in the left kidney, image 1
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  Arteriovenous malformation in the left kidney, image 2