The ductus arteriosus is a blood vessel that connects the blood vessel going to the lungs, known as the pulmonary artery, to the blood vessel going to the body, known as the aorta, in order to allow blood to bypass the lungs in fetal life. A few days after birth, the ductus arteriosus normally closes. If the ductus arteriosus stays open, the child has a condition known as a patent ductus arteriosus, or PDA (Figure 1).
A PDA keeps the connection between the aorta and pulmonary artery open and allows oxygenated or red blood from the higher pressure aorta to flow into the lower pressure pulmonary artery and back into the lungs (Figure 2). With a PDA the left ventricle must pump a higher than normal amount of blood to compensate for the blood that re-circulates through the lungs. The left atrium and ventricle becomes larger or dilated, and the children can develop heart failure (Figure 3).
PDAs are typically closed using a device or coil that is placed in the PDA through a catheter and acts as a plug to close the vessel. PDA closure restores the normal pattern of blood flow and lets the left ventricle return to normal size (Figure 4).
In neonates or infants who are too small to have the PDA closed with a device or coil, surgical closure is performed by tying and/or dividing the vessel.
Visit Houston Cardiovascular Institute Website for more information.