What is ventriculoatrial shunt placement?
Ventriculoatrial shunting (VAS) is a procedure used to treat hydrocephalus that enables the cerebrospinal fluid (CSF) to flow from the brain to the heart's atrium.
Ventriculoatrial shunting (VAS) is a procedure that allows the cerebrospinal fluid (CSF) to flow from the brain to the atrium of the heart. This procedure is typically used to treat a condition called hydrocephalus.
This condition occurs when there is excess CSF in the brain. CSF is a fluid that acts as a cushion for the brain, protecting the brain from an injury due to impact. The fluid also supplies nutrients to the brain and drains away waste products. The CSF normally flows through structures in the brain called the ventricles to the base of the brain and then continues to cover the brain and spinal cord after which the CSF gets absorbed back into the blood.
When the normal CSF flow is disrupted due to impact, there is an excess accumulation of fluid that increases the pressure on the brain (increased intracranial pressure/tension), leading to complications that can damage the brain. The goal of VAS is to divert the CSF away from the brain to the atrium, which is a chamber in the heart, hence reducing the intracranial pressure and restoring the normal CSF flow.
When is ventriculoatrial shunt placement done?
Ventriculoatrial shunting (VAS) placement is indicated for patients with hydrocephalus in whom other treatment modalities and procedures have failed.
Hydrocephalus occurs due to
- Obstruction (partial or complete obstruction of the normal flow of the cerebrospinal fluid [CSF]).
- Poor absorption (the blood vessels are unable to absorb the CSF due to inflammation of the brain or injury).
- Overproduction (CSF is created in excess and quickly compared to the absorption rate).
- Abnormal development of the central nervous system that can obstruct the flow of CSF.
- Lesions or tumors in the brain or spinal cord.
- Bleeding in the brain from a stroke or head injury.
Hydrocephalus in newborns may be due to developmental abnormalities in the brain and nervous system, bleeding in the brain, and infection of the brain during birth.
When is ventriculoatrial shunt placement not done?
Contraindications for ventriculoatrial shunting (VAS) placement include the following:
- Cerebrospinal fluid (CSF) infection
- Systemic infection
- Infection of the heart
- History of shunt-related kidney disease
- Pulmonary hypertension (increased blood pressure of the arteries in the lungs and right side of the heart)
- Heart failure
- Bleeding disorders
How is ventriculoatrial shunt placement performed?
A ventriculoatrial shunt placement involves a few steps to the procedure, as outlined below.
Before the procedure
The physician performs a complete physical examination. They perform a complete blood analysis and radiological assessment of the brain.
The procedure is performed after the patient is given general anesthesia.
During the procedure
The ventriculoatrial shunt is performed under radiological guidance, by placing the tip of a catheter in the ventricle of the brain. The other end of the catheter is placed in the atrium of the heart. The catheter with a valve functions as a unidirectional medium, draining the excess fluid from the brain to the heart. In the heart, the fluid mixes with the blood and gets absorbed.
After the procedure
The patient is administered with intravenous antibiotics and painkillers. Radiological assessment is done after the procedure to ensure that the catheter is positioned correctly.
What are the complications of ventriculoatrial shunt placement?
Complications of ventriculoatrial shunting (VAS) placement may include the following:
- Shunt-induced inflammation of the kidneys
- Microemboli (blood clots in the blood vessels)
- Pulmonary hypertension due to microemboli
- Thrombosis (blood clots) in larger blood vessels
- Endocarditis (inflammation of the heart)
- Wound/cerebrospinal fluid (CSF) shunt infection
- Outgrowing the shunt (as a child with VAS grows, shunt malposition occurs, leading to shunt malfunction)
- Arrhythmia (irregular heartbeat)
- Shunt malfunction
- Delayed intracranial hemorrhage (bleeding into the brain)