Arteriovenous Malformations Treatment in Delhi, India

Arteriovenous malformations are an unusual intertwining of blood vessels between the arteries and the veins that disrupt the normal blood flow and oxygen circulation within the body. Blood flows directly from the arteries to the veins through this entangled complex bypassing the normal capillary bed, resulting in a high-pressure shunt known as a fistula.

The pressure of blood pouring directly from the arteries is too much for the veins to handle. As the veins strive to receive the extra blood, they strain and widen. Blood vessels that are weakened are more likely to rupture and bleed and develop a localised swelling.

Associated Anatomy

Brain and spinal cord

Alternate Names of Arteriovenous Malformations

AVM

Arteriovenous Malformations Causes

AVMs are congenital and are thought to occur as a result of a variety of hereditary disorders, including:

• Cobb syndrome: It is characterised by malformations of the vasculature of the skin, such as wine-coloured birthmarks. It also includes AVMs in the spine, spinal cord, and/or spinal canal.
• Hereditary Hemorrhagic Telangiectasia (HHT): HHT is characterised by AVMs in the lungs, brain, and digestive tract.
• Parkes Weber Syndrome: Several AVMs form in one arm or leg in this condition. These AVMs grow longer and larger than the same limb on the opposite side.
• Wyburn-Mason Syndrome: This condition includes AVMs of the retina and brain, occasionally involving the face.

Arteriovenous Malformations Symptoms

AVMs in the brain

• A terrible headache that resembles a migraine
• Dizziness, nausea, and vomiting
• Seizures
• Stiff neck
• Blood pumping through the AVM causes an odd swishing or ringing sensation in the ear
• Vision difficulties
• Problems with body movement
• Difficulties in speaking as well as understanding
• Mental confusion and hallucination

Spinal AVMs

• Sudden, excruciating backache
• Legs or arms sluggishness
• Paralysis

AVMs in other parts of the body

• Lungs: Shortness of breath; coughing blood.
• Digestive tract: Pain in the abdomen and black stools.
• Limbs: Lumps, swelling, and pain in the arms and legs; muscle weakness or paralysis; numbness or a tingling sensation.

Types of Arteriovenous Malformations (AVM)

Arteriovenous malformation (AVM)

These are intertwined aberrant blood vessels in which arteries shunt straight into veins with no intervening capillary bed, resulting in high pressure.

Cavernoma

This is a low-pressure aberrant cluster of expanded capillaries with no substantial feeding arteries or veins.

Venous malformation

Venous malformation is an aberrant cluster of swollen veins that resembles the spokes of a wheel but lacks feeding arteries. It has low pressure, seldom bleeds, and is usually untreated.

Capillary telangiectasia

It includes aberrant capillaries with expanded portions, similar to cavernoma. It also has low blood pressure and rarely bleeds.

Arteriovenous fistula

It refers to a direct connection between one or more arteries and veins and a sinus where they drain before exiting the skull and heading to the heart. Carotid-cavernous fistulas and dural AV fistulas are the prevalent ones.

Arteriovenous Malformations Diagnosis

• Anterior Circulation Stroke
• Cardioembolic Stroke
• Vein of Galen Malformation
• Intracranial Haemorrhage
• Cluster/migraine Headache
• Cavernous Sinus Syndromes
• Cerebral Amyloid Angiopathy
• Moyamoya Disease
• Cerebral Venous Thrombosis (CVM)
• Chronic Paroxysmal Hemicrania (CPH)
• Dissection Syndromes
• Fibromuscular Dysplasia
• Posterior Cerebral Artery Stroke
• Cerebral Aneurysms

Typical Test of Arteriovenous Malformations

An ultrasound is used to assess the blood flow pattern through the AVM. A CT scan or an MRI determines the extent of the AVM and its proximity to normal bodily areas. An angiography assists the doctors in deciding how to stop blood flow to the AVM by mapping its blood vessels using X-rays.

Arteriovenous Malformations Treatment

Depending on the type, symptoms, and location of the AVM, treatment options range from careful observation to invasive surgery. Some of the symptoms of AVMs can be relieved with medication:

• Anti-seizure drugs are used to treat seizures
• For headaches and back discomfort, pain medications are available

Surgical interventions include:

• Embolisation: In this procedure, a thin, flexible tube (catheter) is inserted to plug the arteries supplying the AVM permanently.
• Sclerotherapy: This procedure involves injecting a drug or a medical-grade material into an AVM to shrink the blood vessels.
• Surgery: Surgery may be suggested if an AVM has bled and/or is in an easily accessible location.
• Stereotactic radiosurgery: This can be used to treat an AVM that is not too large but is located in a region that is difficult to access with traditional surgery.

Risk Factors of Arteriovenous Malformations (AVM)

• Most AVMs are not hereditary. However, a family history may increase the risk of the disease.
• Certain conditions such as hereditary hemorrhagic telangiectasia (HHT) (“Osler-Weber-Rendu syndrome”) may put a person at greater risk for AVM.
• Being a male is a risk factor for brain AVMs.

Possible Complications of Arteriovenous Malformations (AVM)

The possible complication may include but are not limited to seizure, aneurysm (abnormal bulging or swelling in a blood vessel's wall that eventually leads to its rupture), bleeding in the brain leading to coma or death, and/or permanent damage to the brain leading to loss of memory and cognitive impairment.

Prevention of Arteriovenous Malformations

AVMs cannot be prevented since studies believe they are congenital, which means they are there at birth. The ideal method is to react swiftly to emerging symptoms.

Epidemiology of Arteriovenous Malformations (AVM)

• Young adults are typically most affected, with a 30-50 % morbidity rate and a 10-15% mortality rate.
• AVM haemorrhage occurs at a rate of 2 to 3% every year.
• The chance of dying from the first haemorrhage is between 10% and 30%.
• An AVM is nine times more likely to bleed again in the first year after a haemorrhage has occurred.

Expected Prognosis of Arteriovenous Malformations (AVM)

The annual risk of intracerebral haemorrhage remains 2-4%. Those with superficial, moderate-sized AVMs have a fair long-term prognosis and may not benefit from interventional therapy. However, Young AVM patients have a high lifetime risk of bleeding. The prognosis for AVM haemorrhage is better than for other intracerebral haemorrhages. The better prognosis may be attributed to the patients' younger age and higher capacity for reconfiguration of brain function. An angiographic assessment is recommended to define the prognosis of patients with AVM.

Natural Progression of Arteriovenous Malformations (AVM)

The natural progression of the disease involves bleeding and possible seizures leading to a severe neurological deficit, which can be fatal.

Pathophysiology of Arteriovenous Malformations (AVM)

AVMs are congenital lesions composed of a complex vascular conglomerate (called nidus) connected by one or more fistulae. The exact process of forming a complex network of arteries and veins is unknown.

AVMs produce neurological dysfunction through three main mechanisms.

• Haemorrhage mainly in brain parenchyma or maybe in the subarachnoid space and the intraventricular space.
• Alternatively, a seizure is a common (15-40%) consequence of AVM that contributes to the neurologic deficit.
• Rarely, a progressive neurological deficit may occur in 6-12% of patients due to syphoning of blood flow away from adjacent brain tissue ("steal phenomenon")
• Due to the mass effect of an enlarging AVM or venous hypertension in the draining veins.