Arteriovenous malformation (AVM) is a congenital tangle of abnormal blood vessels that can occur anywhere, most often in the brain or spinal cord.
What is arteriovenous malformation?
An arteriovenous malformation (AVM) is an abnormal tangle of blood vessels containing arteries and veins. It is widely unknown as to what causes the tangle, or malformation. AVMs can occur anywhere in the body, but they are most often found in the brain or spinal cord, often referred to as brain AVM and spinal neuro, respectively. They are typically present at birth, but certain genetic changes may also contribute to them developing.
While rare, this cerebrovascular condition can be serious, especially if the AVM ruptures, causing a brain bleed. AVMs are often discovered incidentally during imaging for other conditions, or they are found when they cause symptoms. AHN’s Comprehensive Stroke Clinic and the expert team are experienced in diagnosing and treating AVMs before they rupture. They work in a multidisciplinary manner to deliver personalized care for their patients who are living with AVMs.
Why choose AHN for your arteriovenous malformation care
AHN Stroke Centers are specially equipped to treat strokes and other cerebrovascular diseases that affect blood flow to the brain. Our certified centers are located throughout western Pennsylvania and Erie, so you can find expert care closer to home. Our Stroke Centers are staffed by board-certified neurologists, neurosurgeons, and specialists who work together to deliver the most effective treatment for each patient. Treatment and management are performed by an experienced AHN multidisciplinary team so you can get the care you need, when you need it.
Many AHN Stroke Centers have received advanced stroke center certification by The Joint Commission, an independent, nonprofit organization that evaluates and accredits U.S. healthcare organizations and programs to ensure high standards of quality and patient safety. This designation recognizes the top-level care we provide for even the most complex conditions.
Arteriovenous malformation symptoms and signs
The symptoms and signs of arteriovenous malformation (AVM) can vary from person to person. Some people may not have any symptoms at all and are diagnosed while getting imaging tests for another health condition. Other people can experience one or more of these symptoms:
- Headache
- Seizures
- Weakness or numbness in the arms or legs
- Aneurysm (a bulging or bubble in a blood vessel wall)
- Changes in speech or vision
Causes and risk factors
Doctors and researchers are still unclear as to what causes AVM. Typically, arteries that are responsible for carrying oxygen-rich blood from the heart to the brain, and veins carry oxygen-depleted blood back to the heart. In an AVM, blood flows directly from arteries to veins, bypassing the capillaries that typically slow blood flow and allow for the exchange of oxygen and nutrients. This abnormal connection can lead to several problems resulting in AVM brain condition and AVM neuro condition, which shows up as:
- Bleeding (hemorrhage): The walls of the abnormal blood vessels in an AVM are weaker than normal vessels, making them more prone to rupture and bleeding into the brain or surrounding tissues. This is the most serious complication and can lead to stroke, brain damage, or even death.
- Reduced oxygen to brain tissue: The rapid shunting of blood from arteries to veins means that surrounding brain tissue may not receive enough oxygen.
- Neurological symptoms: Depending on the location and size of the AVM, symptoms can include headaches, seizures, weakness or numbness in parts of the body, problems with coordination, vision changes, or speech difficulties.
The neurology team at AHN has extensive experience in treating individuals with AVM. By personalizing treatment, using advanced technologies, and providing compassionate care, our team can help you achieve improved health outcomes.
Arteriovenous malformation screening and diagnosis
Arteriovenous malformation (AVM) screening and diagnosis typically involve a combination of medical history review, physical examination, and advanced imaging tests. Here's how it's generally done:
- Medical history and physical examination: Physicians will first inquire about your medical history and perform a physical examination to evaluate any symptoms you might be experiencing.
- Imaging tests: Based on the initial assessment, your doctor may order more specific tests:
- CT (computed tomography) or MRI (magnetic resonance imaging) scan: These advanced imaging techniques of the brain can reveal the presence and location of an AVM.
- Cerebral brain angiogram: This is a more detailed test where physicians guide a catheter through your blood vessels. A special dye is injected, which helps to clearly identify and visualize the tangle of abnormal blood vessels in the brain. This test provides crucial details about the AVM, including its size, location, and the risk of bleeding, as well as flow characteristics, which help guide treatment decisions.
These diagnostic tools allow medical professionals to confirm the presence of an AVM, understand its characteristics, and plan the most effective course of action.
Types and grades of arteriovenous malformation
AVM blood vessel tangles can appear in various parts of the body. Types include:
- Brain AVM (Cerebral Arteriovenous Malformation): This is when the twisted blood vessels are in your brain. It's not very common, but it can be serious. If this AVM bursts, it can cause bleeding in the brain.
- Spine AVM (Spinal Arteriovenous Malformation): These happen in your spine, which helps send messages from your brain to the rest of your body. If you have a spine AVM, you might feel weak, numb, or have trouble controlling your bladder or bowels.
- Lung AVM (Pulmonary Arteriovenous Malformation or PAVM): These are in your lungs. They can make you feel out of breath, cough up blood, or even have a stroke because your blood isn't getting filtered properly before it goes to your brain.
- Organ AVM (Visceral Arteriovenous Malformation): These can show up in your insides, like your liver, kidneys, or intestines.
- Arm/Leg AVM (Peripheral Arteriovenous Malformation): These are found in your arms, legs, or other parts of your body that are closer to the surface.
How doctors grade AVMs
Doctors use a special system called the Spetzler-Martin Grading System to figure out how risky surgery might be and to help them decide the best way to treat an AVM. It gives the AVM a grade from 1 to 5 (sometimes 6) based on three things:
- How big the AVM is
- How the blood drains out of the AVM
- The type of brain tissue near the AVM
Each of these gets points. The points are totaled by a doctor for a grade. A higher grade (like 3, 4, or 5) means that surgery is riskier and the treatment might be more complicated.
Arteriovenous malformation treatment
Neurosurgeons and specialized doctors at AHN provide personalized treatment recommendations tailored to your unique needs. Your treatment depends on whether an AVM has caused a brain bleed (which requires immediate treatment) or is causing any symptoms.
At AHN, our team is skilled in performing the most effective treatments for AVM, including:
- Microsurgery: Surgeons remove the AVM, an effective treatment for many patients. We consider several factors before performing this surgery, including the size and location of the AVM, as well as your age and overall health.
- Stereotactic radiosurgery: In this nonsurgical procedure, a physician delivers a focused dose (or multiple doses) of radiation to the affected area, causing the blood vessels to eventually close off. Your physician may recommend this treatment for AVMs that are smaller in size or if you are unable to undergo surgery for any reason.
- Embolization: A physician places a small tube into the affected arteries feeding the AVM and injects a glue-like material into the arteries to block them. This procedure can shrink an AVM, lessening the risk it poses.
Arteriovenous malformation FAQs
Arteriovenous malformation is often a surprising diagnosis that leaves many with questions. To help, we’ve included some of our patients’ frequently asked questions. Your AHN care team is ready to answer any and all questions you have, but this can help set those conversations up, so you feel more confident in your understanding of this condition.
How do you treat an arteriovenous malformation?
Treatment for an arteriovenous malformation (AVM) depends on its size, location, symptoms, and overall health of the individual. The main goals of treatment are to prevent bleeding and to control symptoms. Common treatment approaches include:
- Surgery: This involves surgically removing the AVM. It's often considered for AVMs that are accessible and located in areas where removal can be done with minimal risk to brain function.
- Endovascular embolization: This procedure involves inserting a catheter into a blood vessel and guiding it to the AVM. A glue-like substance or tiny coils are then injected to block off the affected blood vessels, reducing blood flow to the AVM. This can be used alone or before surgery to make the AVM easier to remove.
- Radiosurgery (e.g., Gamma Knife, CyberKnife): This noninvasive treatment uses highly focused radiation beams to target and slowly close off the AVM over several months or years. It's often used for smaller AVMs that are difficult to reach with traditional surgery.
- Observation: For small, asymptomatic AVMs in areas that are difficult to treat, doctors might recommend regular monitoring with imaging scans rather than immediate intervention.
The best treatment plan is determined by a team of specialists, including neurosurgeons, interventional neuroradiologists, and radiation oncologists, based on individual circumstances.
How serious is an arteriovenous malformation?
The seriousness of an arteriovenous malformation (AVM) can vary significantly. Some AVMs may never cause symptoms and are discovered incidentally, while others can be very serious. The most significant risk associated with an AVM is bleeding (hemorrhage), which can lead to stroke, brain damage, disability, or even death. The risk of bleeding depends on factors like the AVM's size, location, and the type of veins involved.
Even if an AVM doesn't bleed, it can cause other problems such as seizures, headaches, and neurological deficits (like weakness or numbness) due to the abnormal blood flow interfering with surrounding brain tissue.
Because of the potential for serious complications, AVMs are generally considered a serious condition that requires careful evaluation and management by medical professionals.
How is arteriovenous malformation diagnosed?
Arteriovenous malformations (AVMs) are typically diagnosed using a combination of neurological examination and specialized imaging tests. The diagnostic process often includes:
- Neurological examination: A doctor will assess your symptoms, reflexes, vision, coordination, and other neurological functions.
- Computed tomography (CT) scan: This imaging test uses X-rays to create detailed cross-sectional images of the brain. These are specialized scans that specifically visualize blood vessels and blood flow, providing clear images of the AVM's structure.
- Magnetic resonance imaging (MRI) scan: MRI uses a powerful magnetic field and radio waves to produce detailed images of brain structures. An MRI is often more sensitive than a CT scan for detecting AVMs and can also reveal signs of previous bleeding or brain damage.
- Cerebral angiography (Digital Subtraction Angiography, or DSA): This is considered the gold standard for diagnosing AVMs. A catheter is inserted into an artery (usually in the groin) and guided to the brain's blood vessels. A contrast dye is then injected, and X-ray images are taken in real-time, providing a very detailed "roadmap" of the AVM's abnormal blood vessels and blood flow.
These diagnostic tools help doctors pinpoint the AVM's exact location, size, and characteristics, which is crucial for determining the best treatment approach.
Can you live with arteriovenous malformation?
Yes, it is possible to live with an arteriovenous malformation (AVM). Some individuals may have an AVM for many years without ever experiencing symptoms, and some AVMs are only discovered incidentally during imaging for another condition. However, living with an AVM does carry risks, primarily the risk of bleeding (hemorrhage) or other neurological complications such as seizures. For this reason, even if an AVM is not actively causing symptoms, doctors often recommend careful monitoring or intervention to reduce these risks, depending on the individual characteristics of the AVM and the patient's overall health.
The decision to treat or observe an AVM is a complex one, made in consultation with specialists, considering the balance of risks associated with the AVM itself versus the risks of treatment.
Is arteriovenous malformation curable?
Yes, an arteriovenous malformation (AVM) can be considered "curable" if it is completely removed or obliterated by treatment. The goal of many AVM treatments, particularly surgery, endovascular embolization, and radiosurgery, is to permanently eliminate the abnormal connection between arteries and veins.
- Surgical removal: If a surgeon can safely and completely remove the entire AVM, it is considered cured.
- Endovascular embolization: While often used to reduce an AVM's size or as a prelude to surgery, in some cases, embolization alone can completely block off the AVM, leading to a cure.
- Radiosurgery: This treatment aims to cause the AVM to gradually close off over time. If follow-up imaging confirms that the AVM has completely disappeared and is no longer supplying blood, it is considered cured.
After treatment, follow-up imaging (like angiography) is typically performed to see if the AVM has been entirely eliminated and that there is no remaining risk of bleeding from it. If a portion of the AVM remains, there is still a risk of rupture, and further treatment may be necessary.
What is the life expectancy of someone with a brain arteriovenous malformation?
The life expectancy of someone with a brain arteriovenous malformation (AVM) is highly variable and depends on several critical factors, primarily whether the AVM ruptures (bleeds) and the effectiveness of treatment.
- Unruptured AVMs: For individuals with an unruptured AVM that causes no symptoms, life expectancy can be normal, especially if the AVM is small or in a less critical location, or if it can be successfully treated. However, there is always an inherent, but sometimes small, annual risk of rupture, which can impact life expectancy.
- Ruptured AVMs: If an AVM ruptures, the outlook becomes more serious. A brain hemorrhage from an AVM can be life-threatening. The mortality rate from a ruptured AVM is estimated to be between 10% and 30% for each bleeding event. Survivors may face neurological deficits or disabilities, which can also indirectly affect long-term health and life expectancy.
- Treated AVMs: If an AVM is successfully treated and eliminated, the risk of future bleeding from that AVM is removed, significantly improving long-term prognosis and potentially leading to a normal life expectancy, assuming no other health complications arise from the AVM or its treatment.
It's important to understand that each AVM case is unique. Regular monitoring and timely medical intervention, when appropriate, are crucial for managing the condition and improving the long-term outlook for individuals with brain AVMs.
Contact us
To schedule an appointment or learn more about AHN neuroscience services, call 412-359-6200.
If you're an existing patient, you can also call (412) DOCTORS 412-362-8677 in Pittsburgh, for Erie call 814-CONNECT, or request an appointment with AHN neuroscience services.