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Learning About Truncus Arteriosus in Newborns

Normal heart and heart showing truncus arteriosus and change in blood flow

What is truncus arteriosus?

Truncus arteriosus (say "TRUNK-us ar-teer-ee-OH-sus") is a type of congenital heart disease. Congenital heart disease refers to heart problems a baby is born with. These heart problems are usually diagnosed at or before birth.

As the fetus develops in the uterus, there is one main artery, or "trunk," leaving the heart. Before birth, that trunk normally splits into two arteries: the aorta and the pulmonary artery.

  • The aorta carries oxygen-rich blood (red blood) from the heart to the rest of the body.
  • The pulmonary artery carries low-oxygen blood (blue blood) from the heart to the lungs to pick up oxygen.

In truncus arteriosus, the trunk doesn't split where it's supposed to. Instead of having two separate arteries leaving the heart, there is one big artery that doesn't split in two until after it leaves the heart. So red blood and blue blood get mixed together. The baby's body doesn't get enough oxygen.

Babies with this problem also have a ventricular septal defect. The two bottom chambers of the heart—the left ventricle and right ventricle—are separated by a wall of tissue called a septum. A ventricular septal defect is a hole in this wall. Some of the blood flows through the hole. So the heart pumps too much blood to the lungs and not enough to the rest of the body.

Your baby may need special care, such as being in the neonatal intensive care unit (NICU). This may be scary for you. But the hospital staff understands this. They will explain what happens and will answer your questions.

How is it diagnosed?

Your doctor may hear abnormal heart sounds, such as a heart murmur, when they examine your newborn.

Your doctor will order tests to find the cause of abnormal sounds or of symptoms. The most common test used to identify this problem is called an echocardiogram, or "echo" for short. It uses sound waves to make an image of your baby's heart.

Other tests, such as an EKG (electrocardiogram), chest X-ray, and checking the amount of oxygen in the blood, also help identify the problem.

A fetal ultrasound, which looks at the baby's heart, may find this problem before birth.

What are the symptoms?

Symptoms may include:

  • A blue tint to the skin, lips, or fingernails.
  • Fast breathing.
  • Sweating while feeding.
  • Not eating well.

How is it treated?

Your doctor will help you understand your choices and what to expect from each of them.

Medicines may be given at first to keep the heart from working too hard.

Surgery is needed to create two separate arteries. If there are other heart problems, they may be repaired at the same time.

What can you expect?

  • You may see tubes and wires attached to your baby. This can be scary to see. But these things help the doctor treat your baby. The tubes supply air, fluid, and medicines to your baby. The wires are attached to machines that help the doctor keep track of your baby's vital signs. These include temperature, blood pressure, breathing rate, and pulse rate.
  • If your baby has trouble breathing, the doctor may use a ventilator. This machine helps your baby breathe. To use the machine, the doctor puts a soft tube through your baby's mouth into the windpipe.
  • The hospital staff will give your baby the nutrition that your baby needs. The doctor may feed your baby through a soft tube that goes through the nose and into the stomach. Or the doctor may use an I.V. that goes through the belly button to do this.
  • Your baby may need oxygen. It is given to the baby through a tube in the nose or throat.
  • Your baby will be kept comfortable and warm.
  • It may seem that your baby is getting lots of tests. All of these tests help your doctor keep track of your baby's condition and give the best treatment possible.
  • Your baby will need routine checkups to check the heart.
  • It's hard to be apart from your baby, especially when you worry about your baby's condition. Know that the hospital staff is well prepared to care for babies with this condition. They will do everything they can to help. If you need it, ask for support from friends and family. You can also ask the hospital staff about counselling and support.

Follow-up care is a key part of your child's treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if your child is having problems. It's also a good idea to know your child's test results and keep a list of the medicines your child takes.

Where can you learn more?

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