Truncus arteriosus (embryology) Tags: Anatomical Structure, Embryology.The truncus arteriosus is a structure that is present during embryonic development. It is an arterial trunk that originates from both ventricles of the heart that later divides into the aorta and the pulmonary trunk. thumbnail Gray page 514 Gray subject 135 MeSH name Truncus+Arteriosus MeSH number A07.541.278.930 Learn more... Loading...