Truncus arteriosus

Truncus Arteriosus

What is truncus arteriosus in newborns?

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.

What are the symptoms of truncus arteriosus in newborns?

Symptoms may include:

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

How is truncus arteriosus in newborns 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.

How is truncus arteriosus in newborns 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.

How can you care for your newborn who has truncus arteriosus?

Your doctor will make sure that you have all the information you need to take care of your baby. Your child's care team can show you how to help your baby. You can also ask the hospital staff about counseling and support.

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The content above contains general health information provided by Healthwise, Incorporated, and reviewed by its medical experts. This content should not replace the advice of your healthcare provider. Not all treatments or services described are offered as services by us. For recommended treatments, please consult your healthcare provider.

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