Hemitruncus
Also known as: hemitruncus arteriosus, pulmonary artery coming from the aorta, PACA, anomalous origin of the right pulmonary artery.
What is hemitruncus?
Normally, the pulmonary artery comes off the right ventricle of the heart and splits into two distinct branches to carry blood to the lungs. With this very rare heart abnormality (hemitruncus), the main pulmonary artery and one branch, typically the left, are found in the correct position, however the right one comes out of the ascending aorta.
What causes hemitruncus?
Hemitruncus is a congenital heart defect of unknown cause.
What are the symptoms of hemitruncus?
Babies with hemitruncus typically have trouble with worsening lung vascular disease and heart failure.This presents as trouble breathing, and poor feeding-weight gain, among other symptoms.
What are hemitruncus care options?
Most neonates/infants with hemitruncus are treated surgically.
Reviewed by: Jack Wolfsdorf, MD, FAAP
This page was last updated on: September 16, 2025 12:29 PM
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