Arteriovenous malformations (AVMs) are tangles of blood vessels that cause abnormal artery-to-vein
connections. Incorrectly formed blood vessels disrupt communication between arteries and veins.
Arteriovenous malformations are found rarely present in about 1 in 100,000 people. AVMs more
commonly occur in the head, neck and spine. Next in frequency are AVMs of the extremities with an
equal distribution between the upper and lower extremities. It is called a peripheral arteriovenous
malformation when the abnormality occurs in the arms, legs, heart, lungs, liver, the reproductive or
genital system. Developments in classification along with imaging and interventional techniques
available at laser vein hospital in Chennai have helped to improve the outcome in the management
of these potentially threatening peripheral AVMs.
have helped to improve the outcome in the management
of these potentially threatening peripheral AVMs.
What Causes Arteriovenous malformation?
It is not certain as to what causes arteriovenous malformations. It is believed to be congenital,
where it develops during pregnancy and the individual is born with an AVM. Some people with head
trauma or certain infections have also reported AVM. AVMs are thought to be hereditary only in rare
cases.
Normal blood flow works following a circulatory network system. Blood circulates through the body
within an organized closed circuit of blood vessels. Arteries carry oxygen-rich blood from the heart
to the brain and the rest of the body parts. Veins return oxygen and nutrient-depleted blood and waste
products from all parts of the body back to the heart and lungs. Normally, the blood pressure in the
veins is much lower than in the arteries. The smallest blood vessel units of arteries and veins called
capillaries connect with each other in the tissues for the exchange of blood. The missing “bridge” of
capillaries between arteries and veins within the vascular tree forms an AVM. The malformation can
occur anywhere between the arterial (arteries) side to the arterial-capillary and the venous (veins)
side. In an AVM, larger channels that connect the arteries directly to the veins replace the capillaries.
carry oxygen-rich blood from the heart
to the brain and the rest of the body parts. Veins return oxygen and nutrient-depleted blood and waste
products from all parts of the body back to the heart and lungs. Normally, the blood pressure in the
veins is much lower than in the arteries. The smallest blood vessel units of arteries and veins called
capillaries connect with each other in the tissues for the exchange of blood. The missing “bridge” of
capillaries between arteries and veins within the vascular tree forms an AVM. The malformation can
occur anywhere between the arterial (arteries) side to the arterial-capillary and the venous (veins)
side. In an AVM, larger channels that connect the arteries directly to the veins replace the capillaries.
As the direct connection diverts the blood from the artery directly to the vein, bypassing the
capillaries, it is called a shunt. The channels are called the “nidus” that may consist of many tiny
shunts or a few large ones. In a peripheral AVM, the blood supply along with its nutrients and oxygen
to the tissue around is reduced because of the nidus. This raises the blood pressure in the draining
veins and increases the amount of blood going through the arteries and veins. This process, when
continued over a period of time, damages the surrounding tissue and loads the heart to work harder
in order to keep up blood circulation.
Symptoms of Arteriovenous malformation
Initial symptoms or problems may not present in most people with AVM. Symptoms may never
appear if they have not appeared until 50 years of age. However, 12% of people with AVMs do have
some symptoms. AVMs grow along with the stages of growth and symptoms change over time.
Hormonal changes during puberty or pregnancy, trauma or injury, and surgery can affect how quickly
the AVM grows. Symptoms are assessed by a team of doctors for varicose vein laser treatment in
Chennai. AVMs are often organized using a scale called the Schöbinger staging system:
-Stage I (quiescence) is quiet with only the skin on top of the AVM being warm and pink or
red.
-Stage II (expansion) when it gets larger with a pulse felt or heard in the AVM.
-Stage III (destruction) causes pain, bleeding or ulcers.
-Stage IV (decompensation) results in heart failure.
Symptoms of AVM vary with the location of the malformation. Brain and spinal AVM often leads to a blood vessels to bleed or rupture, causing stroke and brain damage or neurological deficits such as paralysis and seizures. Symptoms of peripheral arteriovenous malformation depend on their size and the significance of the location, which may include:
-Shortness of breath on exertion
-Coughing up blood
-Abdominal pain
-Black stools
-Lumps on arms, legs or on trunk
-Pain with swelling
-Weakness or paralysis of muscles
-Numbness or tingling sensation
-Skin sores or ulcers
Treatment for peripheral Arteriovenous malformation
AVMs are benign, meaning they are noncancerous. The focus of treatment for AVM is managing the
symptoms and improving the life of the patient. There is no medicine that can cure an AVM. The age
of the patient, the size, location, and stage of the AVM are the deciding factors of a treatment plan.
An AVM without problems may require just regular follow-up visits. Since AVMs can expand over
time, it is recommended to start treatment as early as it presents with symptoms. The force of the
blood flow from arteries cause increased pressure to the AVM. Veins have weak walls that cannot
always withstand the pressure of excess blood flow, causing it to burst and bleed leading to
significant health problems. Symptoms of an AVM in the arm or leg may be eased by wearing a
graded elastic compression sleeve or stocking that squeezes the enlarged veins and reduces the
swelling.
Embolization and sclerotherapy are the treatments that can reduce the size and symptoms of an
AVM. Embolization involves using materials such as medical glue, metal coils or plugs that are placed
into the centre of the AVM to block blood flow. The procedure is done through a tube called a
catheter, which is inserted through an artery or vein connected to the AVM. Blood flow into the AVM
is stopped to help shrink the AVM.
Sclerotherapy is a procedure where a liquid medicine called a sclerosant is injected into the AVM to
destroy the vessels and cause scars to form. It is similar to the technique used to treat other vascular
conditions such as venous insufficiency, varicose veins and lymphatic conditions. Ultrasound imaging
is normally used to reach and target the AVM. Destruction of blood vessels leads to less or no blood
flow through the AVM. Sclerotherapy is often. Such procedures for AVMs should be done only by
surgeons with experience in laser treatment for varicose vein in Chennai.