Transposition of the Great Arteries|Diagnosis & Treatment—Heart Surgery In Babies And Children

What is Transposition of the great arteries (TGA)?

A father shares his side of the story -after his newborn son was treated for Transposition of Great Arteries

Transposition of Great Arteries (TGA) is a common heart defect in newborns. Babies with this heart condition are very blue since birth and have fast breathing.

After oxygen from the blood has been used up by the body- oxygen poor blood turns blue. This Blue blood from the body returns to the Right upper chamber of the heart (Right Atrium) with the help of two veins (SVC and IVC).

From the right atrium (right upper chamber of the heart that collects blood) blood will go to the Right Pumping chamber (Right Ventricle). The Right ventricle then pumps this blue- oxygen poor blood to the lungs (through a tube-like Great Artery-Pulmonary artery).

The Lungs will put Oxygen in this blue blood, making it Oxygen rich and red again. This Red blood returns (with the help of small tube-like pulmonary veins) to the left upper (blood collecting) chamber of the heart- Left Atrium.

From the left atrium this red blood will go to the Left Pumping chamber (Left Ventricle). The Left ventricle then pumps this red- oxygen rich blood to the body (through a tube-like Great Artery- AORTA).

1. There are TWO Great Arteries that come out of the Heart-

AORTA- comes out of the left side of the heart and supplies ‘red’ Oxygen-rich blood from the left ventricle (left pumping chamber of the heart) to the body and
PULMONARY ARTERY- comes out of the right side of the heart and carries ‘blue’ Oxygen-poor blood from the right ventricle (right pumping chamber of the heart) to the Lungs.

2. Transposition of Great Arteries (TGA): in this heart condition these two ‘Great Arteries’ come out from the wrong side of the heart- Aorta comes out of the Right Ventricle and carries the blue blood in the right ventricle to the body and Pulmonary artery comes out of the left ventricle and carries red blood from this left ventricle to the lungs.

3. So- in this heart condition- blue blood that returns from the body is pumped back to the body and red blood returning from the lungs is pumped back to the lungs. This makes this heart condition very dangerous and life threatening -as very little oxygen reaches the body. Unfortunately, without treatment, almost half of the children affected with this heart condition are at risk of dying within the first few weeks of life, so surgery is recommended as soon as possible (usually within 1-2 weeks of life)

4. Treatment of this heart condition is an open-heart surgery- Arterial Switch Operation, in which the great arteries are cut and sutured back to their correct position.

Ideal Age for Transposition Of The Great Arteries Patient

Timing of surgery is based on the presence or absence of a VSD in these children as this will define the natural history in case of untreated disease.

TGA without VSD - Survival without treatment – 80% at 1 week, 17% at 2 months, 4% at 1 year
Usual cause of death- Hypoxia
TGA with VSD – Survival without treatment 91% at 1 month, 43% at 5 months, 32% at 1 year
Usual Cause of Death- Heart failure

TGA without VSD: Surgical Repair is recommended at Diagnosis. Arterial switch operation is best done within 2 weeks of life but can be performed till 4-6 weeks of age. After this age, if the child survives, either a procedure to prepare the LV followed by Arterial Switch Operation (Staged surgery) is performed or a Senning’s operation is done.

TGA with VSD: should undergo an Arterial Switch Operation with VSD closure by 4-8 weeks of life. But these children can usually be sent for treatment till about 6-9 months of age after which most will become inoperable.

Also Read Age for Pediatric Heart Surgery

Why do the surgery?

Transposition of Great Arteries is a life-threatening heart condition and untreated – most babies with this birth defect will not survive.

On the other hand- most children that undergo an Arterial Switch Operation will go on to live a ‘Near Normal’ life.

The surgical procedure

Surgery is usually done immediately after birth or within a few weeks of birth. The surgeon makes an incision down the front of the chest (called a median sternotomy) and divides the breastbone (sternum) in half to get access to the heart. The heart is placed on cardiopulmonary bypass, meaning that a machine takes over the heart’s work of pumping of the blood so the surgeon can enter the heart to repair it.

The repair will consist of the following steps:

Cutting the Great Arteries and Sewing them to their correct positions.
Connecting the coronary arteries to the newly created aorta (connected to the left ventricle)
If a VSD is also present- Fixing this ‘Hole in the heart’ (ventricular septal defect). The hole(s) between the right and left ventricles are usually closed with a patch of fabric made of Gore-Tex™ or Dacron™.

When the breastbone is put back together, stainless steel wires are usually wrapped around the bone to fix it. The surgery will take an average of seven to eight hours from start to finish.

Risks and benefits of the surgery

Risks of any heart surgery include bleeding, infection, stroke, organ damage, requirement for a temporary or permanent pacemaker, or possibly death. However, the risk of these occurring is 2 to 5%.

The benefit of the surgery is for the child (once recovered from the surgery) will have a near normal life expectancy and quality of life. This would mean that the child will not be blue anymore and will not have heart failure symptoms and his/her growth and development will be better. In addition, the risk of death and heart failure are also avoided.

What to expect during the hospital stay

The length of the hospital stay usually varies from seven to 14 days, depending on how quickly the heart recovers. For a few days following surgery, we will take care of your child in the ICU. In the Intensive Care Unit, we will keep a watch on the child’s Heart Rate, Blood Pressure, Respiration and other organ functions. To avoid frequent interruptions in the care of your child, there is a restriction to visitors, however, parents can visit the child.

The child may need to be in the hospital for longer if they experience any of the following:

A fast heartbeat (supraventricular tachycardia or SVT), requiring medications to slow down the heart
Low heart function
Fluid in the chest (pleural effusions), requiring a chest tube that is put in place at the end of surgery to stay in longer or additional chest tubes to be added
Needing longer than usual help from a machine (ventilator) to breathe.

These challenges are part of the normal recovery after surgery in a child with Transposition of Great Arteries.

For a few days after surgery, the child will be on heart medications to improve heart function and will be on in sedation and on a ventilator- to help the heart get stronger.

After the ventilator is removed and the child is breathing on its own- he/she will be sleepy while recovering from and will be under the influence of strong pain medications. It is normal for a child to be confused, thirsty, and irritable.

Going home

The hospital will supply specific discharge instructions, and all instructions from the hospital, cardiac surgeon, and cardiologist should be strictly followed. The child should get back to his or her normal routine upon arrival at home. For the first week, the child may wish to take more frequent naps or wake up occasionally at night.

The child should be seen by his or her cardiac surgeon/ cardiologist within the first 3-5 days after discharge from the hospital. The incision should be kept clean and dry until it is healed. It should also be protected from the sun for a full year. The child should not be picked up under the arms for four weeks following surgery.

Any of the following symptoms should be reported immediately to the cardiologist:

Fever greater than 101,
Redness, puffiness, discharge from the incision, or
Unusual nausea or flu-like symptoms.