A patent ductus arteriosus, or PDA, is a type of heart defect found in babies, usually in premature babies born 8 weeks or more before their due dates.
PDA occurs because the circulation of a fetus is different from that of a baby who has been born. In the fetus, the blood is oxygenated by the placenta, not the lungs. The ductus arteriosus is a fetal connection between the pulmonary artery and the aorta. The ductus arteriosus allows blood to flow from the heart out into the rest of the body, instead of going to the lungs to pick up oxygen.
After birth, when the baby begins to breathe, the ductus arteriosus should close to allow blood to flow to the lungs to become oxygenated. If it doesn’t, a heart murmur may be heard and the baby may develop respiratory distress and poor growth. A PDA may close on its own or medications or surgery may be used to close it.