NCIt definition : An embryonic blood vessel that allows blood to bypass the lungs by connecting the
pulmonary artery and the proximal descending aorta. In the vast majority of neonates
it atrophies at birth, becoming the ligamentum arteriosum.;
Alternative definition : CDISC: An embryonic blood vessel that allows blood to bypass the lungs by connecting
the pulmonary artery and the proximal descending aorta.;