Three types of surgery can remove or reduce an arteriovenous malformation, a tangle of blood vessels that impede blood flow.

An arteriovenous malformation (AVM) is a rare, noncancerous entanglement of blood vessels that prevents blood from flowing between your arteries and veins.

Instead of blood flowing from your arteries through capillaries to your veins, an AVM causes blood to flow directly from arteries into veins. Your capillaries are unable to distribute oxygen-rich blood to cells, which may damage them.

The excessive blood circulating in an AVM may lead to bleeding, especially for young adults. This could cause neurological problems, like seizures or stroke, or may be fatal.

An AVM can develop anywhere in your body. AVMs in the brain or spinal cord are especially concerning due to the bleeding risk. Because only about 12% of AVMs have symptoms, many are discovered during brain imaging tests for another condition.

The usual treatment for most AVMs is surgery to remove them or reduce their size.

Read on to learn about the types of surgery for an AVM and what to expect for each type.

The purpose of AVM surgery is to prevent the possibility of bleeding by removing or reducing the tangled blood vessels.

This allows blood to flow normally through your capillaries.

The following three types of surgery can treat AVMs. A doctor determines the best option based on factors including:

  • the size of the AVM
  • its location
  • whether it has ruptured
  • your age and overall health

Stereotactic radiosurgery

Stereotactic radiosurgery uses focused radiation beams to thicken and close the AVM’s blood vessels without destroying healthy tissue.

It’s the least invasive surgery to treat an AVM. It doesn’t require an incision. This painless procedure uses sophisticated equipment like a Gamma Knife or CyberKnife.

Stereotactic radiosurgery may be used for AVMs that are difficult to reach, or alongside surgical removal or endovascular embolization.

Endovascular embolization

This less invasive type of surgery can only be performed for AVMs that can be reached with a catheter, which is a long, thin tube.

A surgeon inserts the catheter in an artery, guides it to the AVM, and injects materials that stop blood from flowing to the AVM.

Surgical removal (resection)

Surgical removal, or resection, is the only surgery type that completely removes the AVM. It’s the most invasive and riskiest type. Doctors generally only recommend it for an AVM that has ruptured or has a high chance of rupturing.

To lower the risk of complications, a doctor may first use endovascular embolization or radiosurgery to shrink the AVM, making it safer to remove.

All types of AVM surgery may have the following side effects and risks:

Bleeding in the brain may occur during the 24 hours after AVM surgery. According to 2021 research, out of 214 AVM surgeries, two cases of bleeding began at least 24 hours after surgery.

Additionally, each type of surgery may have additional effects:

  • Radiosurgery:
    • bruising, tenderness, or temporary hair loss where a metal plate was attached to your scalp
    • swelling in the treated area
    • tenderness
  • Endovascular embolization:
    • stroke-like symptoms, such as weakness in one arm or leg
  • Surgical removal:
    • soreness, numbness, or itchiness around the incision
    • swelling or bruising around your eyes

AVM surgery survival rate

Adverse outcomes for AVM surgery range from 10% for smaller AVMs to more than 30% for larger ones, according to a 2023 review.

In addition to the AVM size, factors affecting the survival rate include its location and your age.

The three types of AVM surgery range from radiosurgery, which is noninvasive, to resection, which is the most invasive type.

Stereotactic radiosurgery procedure

Stereotactic radiosurgery may take several hours. You may need to repeat this treatment two or three times over a few months.

The steps are generally as follows:

  1. You are given medication that helps you relax. A doctor administers injections that numb your scalp, then uses small pins to attach a circular metal frame to your scalp.
  2. To pinpoint the exact location of the AVM, the doctor may perform a brain imaging test, like a CT scan or MRI.
  3. As you lie on a table, the doctor places a helmet with small holes over the metal frame on your scalp. The table then moves inside a machine that delivers radiation through the helmet holes.
  4. After the radiation is delivered, the table slides out of the machine. The helmet and metal frame are removed from your scalp.
  5. The healthcare team observes you for a while to ensure you’re recovering normally.

Endovascular embolization procedure

This procedure may be performed while you’re asleep under general anesthesia, or you may remain awake and receive medication to relax you. It may take 3–8 hours.

The steps are generally as follows:

  1. A doctor makes a small incision in your groin area or wrist and inserts a catheter into an artery. Viewing X-ray imaging, the doctor guides the catheter to an artery that’s providing blood to the AVM.
  2. The doctor then injects embolizing materials, like small particles, a glue-like substance, or metal coils or plugs, into the artery to harden it and block the flow of blood.
  3. The doctor then removes the catheter and sews the incision.

A similar procedure called sclerotherapy may be used to treat AVMs. It also uses a catheter, but unlike endovascular embolization which blocks blood flow with injected materials, sclerotherapy injects sclerosant. This medication destroys the AVM’s blood vessels.

Resection procedure

For a resection procedure, general anesthesia is used, so you’re asleep during the procedure.

The steps are generally as follows:

  1. A neurosurgeon makes an incision in your scalp, removes a small part of your skull, and, using a microscope, closely examines the blood vessels in the AVM.
  2. With tiny instruments, the neurosurgeon separates and removes the AVM, being careful not to damage any structures around it.
  3. Once imaging equipment shows the AVM is completely removed, the neurosurgeon reattaches the bone to your skull and stitches the incision.
  4. When you wake up, your healthcare team talks with you to make sure you can understand and respond.

Speak with your doctor about any medications you’re taking, and what medications you can take on the day of the surgery.

You will usually be asked not to eat or drink anything for 8 hours before surgical removal or endovascular embolization.

Before surgical removal of an AVM, the hair around the incision site is shaved and your scalp cleaned. For radiotherapy, you may need to use a special shampoo before the procedure. Do not use hairspray or gel.

For endovascular embolization and radiotherapy, wear comfortable, loose clothing.

For radiotherapy, do not wear:

  • contact lenses
  • glasses
  • dentures
  • jewelry
  • makeup
  • nail polish
  • a wig

The recovery depends on the type of AVM surgery.

After AVM surgical removal that has no complications, you’ll probably stay in the hospital for 4–6 days and spend at least the first day in the intensive care unit (ICU).

If bleeding occurs during surgery, you may need to stay longer in the hospital.

Following an endovascular embolization, you may need to stay in the ICU for 1 day, or longer if bleeding occurred.

You’re usually able to go home after radiosurgery, but do plan on having someone drive you to and from your appointment. The medication used during radiosurgery can make you sleepy.

AVM surgery recovery time

You can typically resume your daily activities 4–6 weeks after the surgical removal of an AVM. It may take up to 6 months to fully recover.

After endovascular embolization or radiosurgery, you can generally resume your normal activities the day after your procedure.

In a small 2021 study with 44 people whose AVMs were surgically removed, researchers found that 88% of them had a good outcome 3 months later.

Five people experienced moderate disability associated with bleeding. One person experienced severe disability.

According to a 2022 review of 36 studies that included 2,108 people who had endovascular embolization, 80% experienced obliteration (destruction) of their AVMs, on average.

It may take about 3 years to completely destroy an AVM with radiosurgery. About 70–80% of AVMs are destroyed during this time frame.

Although there’s not much data available on the cost of treatment for AVMs, a 2019 study with 140 people with AVMs who were treated from 2012–2015 found the following average costs:

  • Surgical removal: $74,540
  • Surgical removal with endovascular embolization: $91,948
  • Radiotherapy: $20,917

Several factors determine the cost, including the size of the AVM and whether it has ruptured.

Health insurance and federal government programs may cover some of the cost of AVM surgery. Contact your insurance provider for information specific to your situation.

The following are answers to some frequently asked questions regarding AVM surgery.

How serious is AVM surgery?

Surgical removal of an AVM is considered high risk due to its location in the brain or spine and the possibility of serious complications.

Endovascular embolization and radiotherapy are less invasive and have fewer risks.

What are the chances of surviving an AVM?

It’s possible to live with an AVM. However, bleeding causes temporary or permanent brain damage in 20–30% of cases and death in 10–15% of cases, according to the Brain Aneurysm Foundation.

What is the AVM life expectancy?

The life expectancy of someone with an AVM depends on several factors, such as whether it ruptures, its size and location, the person’s age, and the effectiveness of treatment.

The only way to completely remove an AVM is through resection, but it’s a high risk surgery. Doctors usually recommend it only for AVMs that have ruptured or have the potential to rupture.

Less invasive surgeries are endovascular embolization and radiosurgery. They both reduce the size of the AVM and may obliterate it over time.

A doctor can recommend the surgery that’s best for your particular case.