Introduction:
Arteriovenous malformation (AV) is a formation of an abnormal connection between vein and artery. Hepatic arteriovenous malformations (AVMs) are abnormal connections between the arteries and veins present in the liver. This can cause symptoms, abdominal pain, and fatigue. In addition, these can sometimes cause life-threatening complications, including bleeding and heart failure.
What Are the Causes of Hepatic Arteriovenous Malformations?
The exact cause of hepatic arteriovenous malformations is unknown. Still, it is believed that it is related to abnormal blood vessels in the liver during embryonic development (in the womb), so considered congenital (present at birth). They remain undiagnosed until later in life. Some cases may be associated with other inherited disorders (runs in the family) that affect blood vessel formation. Other factors associated with developing hepatic AVMs include genetic mutations (alteration) and environmental factors such as exposure to various chemicals or toxins. It is also possible for these malformations to occur sporadic (without any known cases).
What Are the Symptoms of Hepatic Arteriovenous Malformations?
Symptoms of hepatic arteriovenous malformations depend on the size and location of the AVM and the patient's health. However, some common symptoms include the following:
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Abdominal Pain - Due to AVM, the blood flow and pressure in the liver increase, which causes pain in the abdomen (upper right side).
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Fatigue - Increased blood flow can lead to anemia (decreased red blood cells or hemoglobin in the blood), which can cause fatigue and weakness in the patient.
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Blood in the Stool - High blood pressure in the liver results in bleeding in the gastrointestinal tract, which can cause blood in the stool.
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Enlarged Liver -The AVM can cause enlargement in the liver, and the liver becomes tender to the touch.
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High Blood Pressure in the Lung - High blood pressure in the lung can cause symptoms such as shortness of breath, chest pain, and cough.
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Heart Failure - In severe cases, the increased blood flow to the liver can cause heart failure.
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Swelling in the Legs - The increased blood flow of the liver results in fluid buildup in the legs. Ultimately it results in swelling and discomfort in the leg of the patient.
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Jaundice - The AVM results in liver damage that causes jaundice (yellow discoloration of the skin and eyes) due to the buildup of bilirubin in the blood.
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Bruising Easily - The AVM can cause bleeding disorders, so patients can easy bruising or have frequent nosebleeds.
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Headaches - AVM also results in headaches.
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Dizziness or Fainting - The AVM can cause changes in blood pressure, leading to dizziness or fainting.
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Abdominal Mass - In some cases, a palpable mass is present in the abdomen.
What Are the Diagnoses of Hepatic Arteriovenous Malformations?
The diagnosis of hepatic arteriovenous malformations involves the following-
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Imaging Tests - Ultrasound, CT (computed tomography scan), and MRI (magnetic resonance imaging) is used to see the blood vessels in the liver. It helps identify abnormal connections between the arteries and veins. These tests can also give information about the size and location of the AVM. These can also detect any associated complications.
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Physical Examination - A physical examination is done to check for signs of liver damage, such as an enlarged or tender liver.
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Lab Tests - Blood tests check for anemia (reduced red blood cell or hemoglobin), blood disorders, or other conditions associated with AVM.
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Angiography - Angiography is a type of imaging test that uses X-rays. It uses a contrast dye to visualize the blood vessels in the liver. This test can provide information about the size and location of the AVM.
What Are the Treatment of Hepatic Arteriovenous Malformations?
Treatment of hepatic arteriovenous malformations depends on the size and location of the AVM. Some standard treatment options include the following:
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Embolization - This is a minimally invasive procedure. It involves blocking the blood flow to the AVM by injecting a substance (such as a coil or glue) into the blood vessels feeding the AVM. This can reduce the blood flow to the AVM and reduce the risk of complications.
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Surgery - Surgery may be an option for larger or more complex AVMs, mainly if embolization is unsuccessful. Surgery can involve removing the AVM or redirecting the blood flow around it.
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Radiation Therapy - Radiation therapy may sometimes shrink the AVM.
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Observation: In some cases, mainly if the AVM is small and not causing symptoms, a doctor may recommend monitoring the AVM with regular imaging tests rather than treating it.
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Transarterial Radioembolization (TARE) - This embolization type uses small beads of radioactive material to block the blood flow to the AVM. TARE also results in the shrinkage of the AVM.
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Transjugular Intrahepatic Portosystemic Shunt (TIPS) - This procedure creates a new connection between the portal and the hepatic vein to redirect blood flow around the AVM. TIPS reduces the pressure in the liver and prevents complications, including bleeding or heart failure.
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Liver Transplant - In some cases, a liver transplant may be considered a treatment option if the AVM damages the liver.
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Medical Therapy - Medications may be used to manage symptoms or prevent complications. For example, blood thinners reduce the risk of bleeding, or some medications may be used to treat heart failure.
Is Hepatic Arteriovenous Malformations Fatal?
Hepatic arteriovenous malformation is a severe condition. It can be fatal. The high blood flow and pressure in the liver can cause liver damage and failure. The risk of complications and death from AVMs varies and depends on the AVM's size and location. AVMs near vital organs, such as the brain or heart, are fatal. Large or rapidly growing AVMs are generally at higher risk for developing complications.
Conclusion:
An abnormal creation of a group of blood arteries in the body results in arteriovenous malformations (AVMs). These abnormal blood vessel configurations bypass healthy tissues by tying together directly and becoming unusually knotted. Typically, this takes place either just before birth or soon after birth. Most AVM sufferers do not initially exhibit any symptoms or issues. Instead, the problem is uncovered when medical professionals look for another unrelated health issue. An AVM can occasionally cause a bursting of the blood vessel to burst. AVMs are sometimes only discovered during an autopsy, which occurs after death. Early diagnosis and prompt treatment prevent further complications, so people should visit a doctor as soon as they notice any related symptoms.
