A 3-day-old boy delivered at 32 weeks of gestation is experiencing respiratory distress syndrome. The physician detects a heart murmur characteristic of a patent ductus arteriosus, a diagnosis that is confirmed with an echocardiogram. Which embryonic structure is involved in this diagnosis?
|A.||Left third aortic arch|
Right third aortic arch
Left sixth aortic arch
Answer C) Left sixth aortic arch
Patent ductus arteriosus (PDA) is a condition in which the ductus arteriosus, a blood vessel that allows blood to bypass the baby’s lungs before birth, fails to normally close after birth.
The ductus arteriosus is derived from the distal portion of the left sixth aortic arch.