What is ligamentum arteriosum?

The ligamentum arteriosum, also known as the arterial ligament, is a small fibrous band that connects the pulmonary trunk to the aorta in the human body. It is a remnant of the ductus arteriosus, a fetal blood vessel that shunts blood flow away from the lungs during fetal development.

After birth, the ductus arteriosus normally closes and becomes the ligamentum arteriosum within the first few days of life. The ligamentum arteriosum helps to maintain the separation of oxygenated and deoxygenated blood in the circulatory system by preventing blood from flowing between the aorta and pulmonary trunk.

The ligamentum arteriosum has no known significant function in adult humans, as blood flow between the pulmonary and systemic circulations is fully established after birth. However, it can still be a useful anatomical landmark for surgeons and radiologists. In some cases, the ligamentum arteriosum may calcify with age, but this is generally benign and does not typically cause any health problems.