Truncus arteriosus is a heart defect that is present at birth (congenital).

Truncus arteriosus occurs when the two main blood vessels, the aorta and the pulmonary artery, don’t separate completely as the fetus develops. A hole in the wall between the two lower chambers of the heart (ventricular special defect) can also be present.

The blood that passes through this combined vessel has a lower oxygen content than normal. Because of this, babies with truncus arteriosus will have blue skin, lips and nailbeds (cyanosis).

Specific treatment for truncus arteriosus will be determined by your child's physician based on:

• Your child's age, overall health and medical history
• Extent of the condition
• Your child's tolerance for specific medications, procedures or therapies
• Expectations for the course of the condition
• Your opinion or preference

Truncus arteriosus must be treated with surgery. However, medical support may be necessary until the best time for the operation to take place. Treatment may include:

Medical Management
Many children will eventually need to take medications to help the heart and lungs work better.

Adequate Nutrition
Infants may become tired when feeding and may not be able to eat enough calories to gain weight. Options that can be used to ensure your baby will have adequate nutrition include: 

• High-calorie formula or breast milk: Special nutritional supplements may be added to formula or pumped breast milk. These will increase the number of calories in each ounce. Your baby will drink less but still get enough calories to grow.
• Supplemental tube feedings: Food can be given through a small, flexible tube that passes through the nose and into the stomach. This can either add to or take the place of bottle feedings.

Surgical Repair
Surgery is usually performed after the infant is 2 weeks old. It is done this early so the blood vessels in the lungs are not damaged by the extra blood flow. The pulmonary arteries are detached from the common artery (truncus arteriosus). They are connected to the right ventricle using a section of pulmonary artery from a tissue donor (homograft). The ventricular septal defect is closed with a patch.