arteriosus

Arteriosus is a term used in anatomy and medical terminology to denote an arterial structure or an artery. Derived from Latin, it is commonly used as part of compound names describing arterial vessels. The most well-known example is the ductus arteriosus, a fetal blood vessel that connects the pulmonary artery to the descending aorta. This connection allows blood to bypass the lungs, which are not yet functional before birth.

In normal development, the ductus arteriosus closes shortly after birth as the circulatory system adapts to breathing air and the drop in prostaglandin levels. The resulting fibrous remnant is the ligamentum arteriosum. If the ductus arteriosus fails to close, a condition called patent ductus arteriosus (PDA) occurs. PDA can create a left-to-right shunt, increasing pulmonary blood flow and potentially leading to respiratory issues, heart failure, or growth problems if untreated. Treatment options include pharmacologic closure with prostaglandin synthesis inhibitors such as indomethacin or ibuprofen, especially in preterm infants, and various catheter-based or surgical closure techniques for persistent or larger openings.

Beyond the ductus arteriosus, the term arteriosus appears in anatomical nomenclature to describe arterial structures in humans and other animals. It does not refer to a single singular vessel but functions as a descriptive element in the naming of arteries and related structures. In clinical practice, the focus is typically on the ductus arteriosus and its closure, with PDA serving as the most common and clinically significant use of the term. See also arteriosclerosis and ductus arteriosus.