Anomalous origin of one pulmonary artery from ascending aorta 2012-04-09T10:34:29Z Origin of a pulmonary artery from the aorta is also known as hemitruncus. One pulmonary artery branch, usually the right, arises from the ascending aorta just above the aortic sinuses, while the main pulmonary artery and the other pulmonary branch arise in their normal position from the right ventricle. Fyler:550 Anomalous origin of one pulmonary artery from the ascending aorta with the contralateral pulmonary artery arising from the right ventricle. HP:0011660 UMLS:C4021134 Fyler:0550 Hemitruncus Abnormal pulmonary artery morphology