Arteriovenous Malformations and Arteriovenous Fistulas
“I woke up in the hospital; I didn’t know what was going on”
Arteriovenous Malformations (AVMs) are abnormal connections between your
high-pressure arteries and low-pressure veins usually appearing as a tangle
of many of these blood vessels. These tangles frequently develop in a
developing fetus, or around the time of birth. In some cases, these malformations
can be completely benign, and incidentally found while evaluating other
problems. However, AVMs more commonly are found having caused bleeding
in the brain, or compression of parts of the brain which resulted in weakness,
numbness, vision loss, or the inability to speak.
Arteriovenous Fistulas (AVFs) are similar to AVMs although usually involve
a direct connection between arteries and a vein resulting in the same
high pressure to low pressure shunt. These can be congenital (formed around
birth), although often they either develop through life due to:
Tobacco abuse (Cigar, cigarettes, vaping, and dip)
High blood pressure
Drug abuse (including cocaine, heroin/opiates, PCP)
Severe head trauma
Treating a bleeding AVM or AVF
If these abnormal connections have bled, the target of therapy is to disconnect
the abnormal connection between vessels, or to occlude the abnormal, bleeding
vessel. This can be done through an endovascular procedure—one performed
inside the blood vessels using a special glue-like chemical to block flow,
or by using coiling to occlude the bleeding malformation. If the AVM/AVF
cannot be fully treated from the inside, some malformations can be treated
through a traditional neurosurgical procedure. In some cases, targeted
gamma-knife therapy can be used to prevent the risk of bleeding.
The determination for which of these procedures is most appropriate will
be made by your neurosurgeon based on the location, size, and shape of
the malformation.
Treating Asymptomatic AVM or AVF
If a malformation has not bled, there are opportunities to evaluate the
AVM/AVF and determine the safest strategy for treatment. Treatment will
depend on many elements including the following:
Location of the AVM/AVF
Blood vessels involved
Size
Shape
Depending on these characteristics, a treatment plan will be custom tailored for you.
Such a plan will weigh the risks of the malformation compared to the inherent
risks associated with any surgery. It also allows for preparations to
be made to treat including ordering specialty equipment and pretreating
any comorbid illness.
