Dr Ira Shah
Consultant Pediatrician - B.J.Wadia Hospital for Children
Editor - Pediatric Oncall

What is truncus arteriosus?
The normal heart consists of 4 chambers and two arteries - the aorta which supplies the pure blood to the body and the pulmonary artery that supplies impure blood to the lungs. In truncus arteriosus, only one artery arises from the heart. Thus both pure and impure blood mix and go to lungs and the body. As a result every organ of the body receives less oxygen and the patient looks blue due to less oxygenated blood. The pulmonary artery arises a little away from this common artery to go to the lungs. Since both arteries are from the common artery, the ventricles of the heart also have a large hole in the septum which intermingles both oxygenated blood and impure blood together.

What are the symptoms of truncus arteriosus?
Since both pure and impure blood mix together, the child appears blue. Also since both ventricles of the heart pump into a common artery and pulmonary artery opens a little away in the common artery, more blood goes into the pulmonary artery that increases blood circulation in the lung and cause breathlessness. Because less blood goes to the rest of the body and oxygen content of the blood is also less, the body’s demand for oxygen is not met. Thus the heart has to pump even more leading to heart dysfunction can lead to increased sweating, poor feeding and inability to put on weight. Most patients without surgery would not survive till 1 year of age. Rarely, untreated patients of truncus arteriosus would survive into adulthood.

What is the treatment of truncus arteriosus?
Surgery usually early in life is required. It includes closing the hole between the two ventricles of the heart, detaching the pulmonary arteries from the large common artery and connecting the pulmonary arteries to the right ventricle with a tube graft. Patients with surgical repair also need regular follow up for a long time in form of routine clinical and echocardiographic follow up.

What is the prognosis of a patient with truncus arteriosus?
Among patients surviving the early post-operative period, the prognosis is generally very good. Prognosis appears less favorable for patients with accompanying complicated heart conditions.