Your circulatory system consists of
your heart and blood vessels. There are three types of blood vessels in the
circulatory system: veins, capillaries, and arteries. Arteriovenous
malformations (AVMs) are defects in the blood vessels of the circulatory system.
A malformation is an abnormal
connection between the veins and arteries. This interferes with your
body’s ability to circulate blood. It’s usually congenital, which means
the condition is typically present at birth. Although malformations can begin anywhere
in your body, some develop in the brain and spinal cord region, causing
seizures and headaches.
What Causes AVMs?
What causes AVMs is unknown. Some
doctors believe they occur in the womb or shortly after birth and appear later
as the child ages.
Children born with an AVM condition
may have a bluish tint to their skin. This is due to the absence of oxygenated
blood circulating through the body. The skin tends to darken to a deep red or
purple as children age and the condition worsens.
Who Is at Risk for Arteriovenous
If you have family members who have
AVMs, you’re at greater risk. A history of unexplained bleeding may also
place you at risk for AVMs.
What Are the Symptoms of AVM?
The symptoms of AVM vary, depending
- location of the AVM
- size of the AVM
- risk factor for the AVM
- type of blood vessel involved in the AVM
You may not have significant symptoms
if you have an AVM in the brain. In some cases, brain AVMs may cause headaches
or seizures. Unfortunately, due to lack of symptoms, this type of AVM often
goes undiagnosed or unnoticed until it presents life-threatening
symptoms for AVMs found in the brain include:
- bleeding in the skull
- memory lapses
If the AVM is elsewhere in the body,
the symptoms may be more pronounced.
symptoms for AVMs found in the limbs and spinal cord include:
- muscle weakness
- inability to move a limb
- lack of coordination
symptoms for AVMs found in the organs, chest, or abdomen include:
- abdominal pain
- back pain
- chest pain
- irregular sounds in the affected blood vessels
symptoms in children under age 2 include:
- congestive heart failure (the heart is unable to
pump out the blood enters it)
- hydrocephalus (an increase in fluid in the brain
that causes swelling)
How Are AVMs Diagnosed?
Your doctor will perform a physical
examination and several tests to confirm an AVM. It’s important to rule out
other health problems that can mimic the symptoms of AVMs.
Imaging tools and methods used to
diagnose AVMs include:
- CT scan: an imaging tool used to produce
detailed images of the inside of the body
- angiography: determines how well the blood
circulates in the body
- magnetic resonance angiogram (MRA): produces
images of the blood vessels
How Are AVMs Treated?
Your treatment plan will depend on
your age, condition, and physical health. The most important goal is to prevent
internal bleeding, which can lead to stroke or death.
Your doctor might prescribe
medications even though they don't cure AVMs. Medications control pain and
Surgery to repair or remove damaged
blood vessels is an option. The type of surgery you’ll need depends on your
type of AVM. There are three options:
- conventional surgery
- endovascular embolization
Endovascular embolization is used for
arteriovenous malformations deep in the brain or spinal cord tissue. In this
procedure, a thin, flexible tube called a catheter is guided to the AVM to
close up the abnormal connection. It doesn’t repair the AVM, but it reduces
blood flow to it and makes surgery safer.
Radiosurgery involves using a highly
concentrated beam of radiation and focusing it directly on the site of the AVM.
The radiation damages the walls of the blood vessels leading to the AVM, but it
doesn’t always destroy the AVM itself.
What Is to Be Expected in the Long Term?
AVMs can’t be prevented. However, you
can manage and treat symptoms with proper medical care. Taking prescribed
medications can help avoid bleeding problems, pain, and other complications.
Managing high blood pressure, avoiding
medications that thin the blood, and keeping regular appointments with a
neurologist can also help monitor your condition and prevent complications.