Truncus arteriosus is a rare heart birth defect in which a baby is born with one large vessel, instead of two separate vessels, leading out of the heart. In truncus arteriosus, the two lower chambers of the heart are also missing a portion of the wall dividing them. The condition results in severe circulatory problems because the oxygen-poor blood that should go to the lungs and oxygen-rich blood that should go to the rest of the body are mixed together. Babies with truncus arteriosus can develop respiratory problems, high blood pressure in the lungs, enlarged hearts and heart failure.
It’s not entirely clear what causes truncus arteriosus, but risk factors may include a viral illness during pregnancy; poorly controlled diabetes during pregnancy; use of certain medications during pregnancy; and certain chromosomal disorders, including Down’s syndrome, DiGeorge’s syndrome or velocardiofacial syndrome.
Symptoms of Truncus Arteriosus
The symptoms of truncus arteriosus may resemble other medical conditions or heart problems. While each baby with this condition may experience different sets of symptoms, the most common signs of truncus arteriosus include:
- Cyanosis (bluish coloring)
- Pale skin
- Cool skin
- Rapid breathing
- Heavy breathing
- Rapid heart rate
- Congested breathing
- Disinterest in feeding, or tiring while feeding
- Poor weight gain/growth
- Excessive fatigue or sleepiness
- Excessive sweating
Treatment of Truncus Arteriosus
Left untreated, truncus arteriosus will usually kill a child within the first year of life. However, surgery can repair truncus arteriosus in an infant, though multiple procedures may be needed. Among other things, a surgeon will implant a tube called a conduit, along with a valve, to connect the right ventricle with the upper portion of the pulmonary artery — creating a new, complete pulmonary artery. Most infants with truncus arteriosus have surgery within the first two months of life. As the child gets older, one or more follow-up surgeries may be needed to replace the conduit as they grow.
Once the defect is corrected, a child with truncus arteriosus will need lifelong follow-up care with a cardiologist. The doctor may recommend that the child limit physical activity, particularly intense competitive sports. Children born with truncus arteriosus will also need to take antibiotics before dental procedures and other surgical procedures to prevent infections.