Balloon atrial septostomy is a procedure usually associated only with treating congenital heart defects in newborns. This is because over the normal course of development, the muscular wall (septum) between the atria generally becomes too thick for a balloon to be used.

A  variation of balloon atrial septostomy, known as a graded balloon dilation atrial septostomy, has been used in adults to treat pulmonary hypertension. In this procedure, the physician initially uses a needle to create a tiny hole in the septum between the atria. The abnormally increased pressure in the right side of the heart caused by pulmonary hypertension allows blood to flow from the right atrium to the left atrium, creating a right-to-left shunt. Larger balloons are successively used to widen the hole. This procedure relieves the pressure on the right side of the heart, thereby hopefully preventing right-sided heart failureheart failure.

However, early studies have shown a high rate of mortality associated with the procedure, making it difficult to predict which patients will benefit. It is recommended that patients seek a physician and medical facility with a great deal of experience in balloon atrial septostomy in adults. Also, studies have found that older patients and those with impaired kidney function may not be good candidates for balloon atrial septostomy.