ASD, or atrial septum defect, is a hole in the wall between the upper chambers of the heart. ASD, which occurs due to congenital reasons, may close spontaneously in infancy or early childhood. However, if ASD does not close and continues for a long time, it damages the heart and lungs. ASD does not usually cause any symptoms in children. However, with advancing age, heart palpitations, murmurs, leg and abdominal pain...