The result of that is, if it's a large hole, there is blood going from the high-pressure side of the heart, that's the left side, across that atrial septal defect to the right side, so it increases the blood flow to the lungs, and it increases the amount of blood being handled by the right side of the heart.
JACQUELINE NOONAN, MD: In a very large atrial septal defect, it can cause symptoms, but a small atrial septal defect may not cause any symptoms, and in fact this is one of the few kinds of heart disease where somebody might not be diagnosed with it until they were already an adult. Most kinds of congenital heart disease are recognized sometimes as early as right after birth or even before birth.
SPENCER B. KING, III, MD: Many people tolerate them forever, their whole life, and die of something else and never know they have them. But in general, when they're discovered, if there is a substantial shunt of blood, the blood flowing from the left to the right, then those are recommended for closure.