BTT Shunt

What is a BTT shunt?

A BTT shunt operation, or Blalock-Taussig-Thomas shunt, is a procedure to help babies who aren’t getting enough oxygen. This can happen because of a congenital (present at birth) heart condition.

Infants with certain types of heart issues have trouble getting blood to their pulmonary artery, which takes blood to their lungs. When blood goes to your lungs, it picks up oxygen from the air you breathe into your lungs.

A Blalock-Taussig-Thomas shunt is a short-term solution for babies until they grow and develop enough to have a more permanent surgery. During that later operation, a surgeon will remove the BTT shunt and do a more permanent repair. Surgeons usually perform a BTT shunt procedure during a baby’s first few days of life.

For some babies, a BTT shunt is the only solution that works in their situation, even in the long term.

Healthcare providers called this a BT shunt or Blalock-Taussig shunt in the past. The extra “T” for “Thomas” now recognizes a third contributor who helped develop the procedure in the 1940s.

What conditions may need a BTT shunt?

A BTT shunt operation can help babies born with heart conditions that make it hard for them to get enough blood flow to their lungs. These conditions include:

• Hypoplastic left heart syndrome.
• Tetralogy of Fallot (TOF).
• Truncus arteriosus.
• Ebstein’s anomaly.
• Pulmonary atresia.
• Tricuspid atresia.
• Some forms of transposition of the great arteries.

How common is a BTT shunt?

A BTT shunt operation isn’t common. About 1% of babies born each year in the U.S. have a congenital heart defect. Only some of them need a Blalock-Taussig-Thomas shunt.

Also, with today’s medical advances, surgeons don’t perform as many BTT shunts as they once did. In the past, surgeons had fewer options and relied on the surgery more.

What happens before my baby’s BTT shunt?

Your child’s provider will gather information to prepare for the surgery. They’ll do a physical exam and review your child’s medical history. This includes their history during your pregnancy. They may also order tests (most of which are painless and noninvasive), like:

• A transthoracic echocardiogram.
• A coronary angiogram or CT angiogram (in some cases).
• Blood tests.
• Chest X-ray.
• Electrocardiogram (EKG).
• Genetic testing.

You should also receive instructions about bathing your child and when they have to stop eating and drinking before surgery.

What is the difference between a BTT shunt and a modified BTT shunt?

In the original BTT shunt procedure (which healthcare providers virtually never perform today), surgeons connected a baby’s subclavian artery (near their collarbone) to their right pulmonary artery. In the modified version providers use today, surgeons use a synthetic fabric graft to connect the two arteries.

Like the original method, the modified version allows your subclavian artery to improve your body’s overall circulation. But it does this without sacrificing how much blood it can supply to your arm (which is one of its functions). It also gives a surgeon more flexibility in connecting the two arteries.

What happens during a BTT shunt operation?

During a BTT shunt procedure, a surgeon will:

1. Access your baby’s chest by cutting through their breastbone (sternum).
2. Remove all of their thymus to access their heart.
3. Attach a synthetic graft between your child’s subclavian artery and right pulmonary artery.
4. Check to see if the graft is working well and has no leaks or blood clots.
5. Close your child’s chest.

How long does a BTT shunt take?

A BTT shunt procedure takes several hours. The amount of time will vary depending on your child’s specific case. You should receive updates from providers at times throughout the surgery.

What happens after a BTT shunt?

After Blalock-Taussig-Thomas shunt surgery, your child will receive heparin, a blood thinner (anticoagulant) that prevents blood clots. They’ll also receive aspirin, which they’ll need to take their whole life. Rarely, babies need ECMO (temporary life support) after surgery.

You may need to prepare yourself emotionally to see your baby after surgery. They’ll have tubes and wires that connect to them, which may be hard to look at. But each piece of medical equipment has a purpose in helping your child heal.

What are the benefits of a BTT shunt?

A BTT shunt procedure can help your baby deliver more oxygen to cells throughout their body. It should help with the bluish tint on their skin that comes from a lack of oxygen.

The surgery may be a bridge to get your child to their next surgery, which is a more complete repair. Or it may be the surgery that’s best for them now and in the long run.

What is the mortality rate for BTT shunts?

Mortality rates from various studies range from about 7% to about 14%.

What are the risks or complications of a BTT shunt?

Complications of a BTT shunt may include:

• Too much blood going to your pulmonary artery and lungs (pulmonary overcirculation).
• Blood clots.
• Injury to a nearby nerve, especially the nerve that gives deepness to your child’s voice.
• Abnormal heart rhythm (arrhythmia).
• Cardiac arrest.

What is the recovery time?

Your child will likely spend two weeks in the hospital after receiving a Blalock-Taussig-Thomas shunt. During the first week or more, they’ll be in the intensive care unit (ICU). After going home, your child will need regular checkups with their provider. The first in-person appointment will likely be a week or two after going home. If your hospital has a program that uses technology to monitor babies at home, a provider will enroll your child.

When should I call my healthcare provider?

Contact your healthcare provider if your child has:

• Swelling.
• Redness.
• A bluish color.
• Lethargy (excessive tiredness).
• Fever.
• Fluid coming out of the surgical area.

A note from Cleveland Clinic

Like any parent, you want your baby to have every advantage you can give them. The way to give them that advantage now is by asking questions about the options available to them. You can choose a surgeon and facility that has years of experience doing heart procedures on children like yours. This can give you peace of mind when deciding what’s best for your child.