What is Truncus Arteriosus?
Truncus Arteriosus is a heart defect in newborns in which only one artery comes out of the heart and supplies blood to the Body and the Lungs. Babies with this heart condition are a little blue since birth and have fast breathing and difficulty feeding.
Normally- After oxygen in 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).
So- as you would understand- Normally- 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.
In Truncus Arteriosus there is only ONE artery that comes out of the Heart (Truncal Artery) and supplies blood to the Lungs and the body. There is also a VSD (Hole in the wall separating the two pumping chambers of the heart -the right and left ventricles).
Unfortunately, among the babies with this heart condition, without treatment, only about 50% survive beyond the 1st month, 30% beyond 3 months, only 15% are alive by 6 months of age and only 10% survive beyond 1 year, so surgery is recommended as soon as possible (usually within the first few weeks of life)
Treatment of this heart condition is an open-heart surgery- A surgical repair in which the VSD is closed in such a way that blood from the left side of the heart will go through the single great artery. Then the artery going to the lungs are removed from the Truncal Artery and connected to the right side of the heart (Right Ventricle) using a Tube-like implant.
Why do the surgery?
Truncus Arteriosus 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 a Corrective Operation will go on to live a much longer life. However, as these babies grow- they will need a change of the implant to a bigger size, usually 2-3 times in a lifetime.
The surgical procedure
Surgery is usually done 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:
1. VSD - 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™.
2. Cutting and Removing the Pulmonary artery (artery going to the lungs)- from the Truncal Artery and connecting it to the Right Ventricle using a Tube-like Implant.
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. The risk of these occurring is about 8-9 %.
The benefit of the surgery is (once recovered) that the child will have a relatively 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.
However, as these babies grow- they will need a change of the implant to a bigger size (usually 2-3 times in a lifetime).
What to expect during the hospital stay
The length of the hospital stay usually varies from 9 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 Truncus Arteriosus.
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:
- (1) fever greater than 101
- (2) redness, puffiness, discharge from the incision, or
- (3) unusual nausea or flu-like symptoms.
In the initial phase of follow up we see the child frequently, but after a few months- the follow up is usually limited to once a year to plan a change of the implant at the appropriate time.
