Overview

Truncus arteriosus (TRUNG-kus ahr-teer-e-O-sus) is a rare heart defect that's present at birth (congenital). If you or your baby has truncus arteriosus, it means that one large blood vessel leads out of the heart. Normally, there are two separate vessels coming out of the heart.

In addition, there is usually a hole — known as a ventricular septal defect — between the two lower chambers of the heart. As a result of truncus arteriosus, oxygen-poor blood that should go to the lungs and oxygen-rich blood that should go to the rest of the body are mixed. This creates severe circulatory problems.

Untreated, truncus arteriosus can be fatal. Surgery to repair truncus arteriosus is generally successful, especially if the repair occurs before your baby is 1 month old.