What vessels are involved in a patent ductus arteriosus?

In a patent ductus arteriosus (PDA), the main vessels involved are the pulmonary artery and the aorta. The ductus arteriosus is a fetal blood vessel that connects the pulmonary artery to the aorta, allowing blood to bypass the non-functioning fetal lungs. After birth, this duct usually closes as part of the normal physiological changes, but if it remains open (patent), it creates a shunt where oxygenated blood from the aorta flows back into the pulmonary artery. This can lead to increased blood flow to the lungs and other associated complications.

The involvement of the pulmonary artery and aorta is critical to understanding the pathophysiology of PDA, including how it can lead to heart failure and pulmonary hypertension if left untreated. This is distinct from other options that involve different chambers or vessels not typically associated with the ductus arteriosus, reflecting a fundamental understanding of both fetal and postnatal cardiovascular anatomy.