Also known as the Rashkind procedure, a balloon atrial septostomy is a catheter-based procedure that widens a heart defect called an atrial septal defect (ASD), which is a hole between the two upper chambers of the heart (atria). An ASD is a congenital heart defect, meaning it is present in babies at birth. The procedure is performed when the infant also has one or more additional heart defects that result in abnormal circulation throughout the heart. In these cases, the ASD is often necessary for life because it provides a pathway for oxygenated blood to be pumped out to the body. Thus, the Rashkind procedure is a palliative procedure, or a temporary solution to improve circulation until underlying cardiac defects can be repaired.

When a balloon atrial septostomy is successful, the baby will no longer have a bluish tint (cyanosis) to its skin, lips, fingernails and other body parts, a condition often called blue baby.

In general, a balloon atrial septostomy is performed on infants who are 2 or 3 weeks old when they have been diagnosed with one or more congenital heart defects, such as:

• Transposition of the great arteries. A heart defect in which the aorta (the main artery carrying oxygen-rich blood to the body) and the pulmonary artery (the main artery carrying oxygen-poor blood to the lungs) are in reversed positions. 
  
  
• Total anomalous pulmonary venous return (TAPVR). A heart defect in which the pulmonary veins between the lungs and the heart are not connected properly. As a result, oxygen-rich blood returning from the lungs to the heart is detoured through the bad connection and mixed with oxygen-poor blood coming back to the heart from the rest of the body.
  
  
• Double outlet right ventricle. In this defect, both the great vessels (e.g., aorta and pulmonary artery) arise from the right ventricle.
  
  
• Pulmonary valve disease. Any disease that causes significant obstruction of the pulmonary valve, which lies between the right ventricle and the pulmonary artery. For example, pulmonary atresia, in which the leaflets of the pulmonary valve are fused, might require a balloon atrial septostomy.

A balloon atrial septostomy may not be performed on infants over the age of 1 to 2 months because the muscular wall (septum) between the atria may have become too thick for the balloon. For these infants, another procedure called blade atrial septostomy may be used to enlarge the tiny hole in the septum between the atria. The physician may sometimes need to perform a septostomy to create a hole in the first place to improve cardiac circulation until the other heart defect(s) can be repaired.