Concept
Atrial septostomy is a surgical procedure in which a small hole is created between the upper two chambers of the heart, the atria. This procedure is primarily used to palliate dextro-Transposition of the great arteries or d-TGA (often imprecisely called transposition of the great arteries), a life-threatening cyanotic congenital heart defect seen in infants. It is performed prior to an arterial switch operation. Atrial septostomy has also seen limited use as a surgical treatment for pulmonary hypertension. The first atrial septostomy (then less precisely called a septectomy) was developed by Vivien Thomas in a canine model and performed in humans by Alfred Blalock. The Rashkind balloon procedure, a common atrial septostomy technique, was developed in 1966 by American cardiologist William Rashkind at the Children's Hospital of Philadelphia. There are two types of this procedure: balloon atrial septostomy (also called endovascular atrial septostomy, Rashkind atrial balloon septostomy, or simply Rashkind's procedure) and blade atrial septostomy (also called static balloon atrial septostomy). In a normal heart, oxygen-depleted blood ("blue") is pumped from the right side of the heart, through the pulmonary artery, to the lungs where it is oxygenated. This is the pulmonary circulation part of blood flow. The oxygen-rich ("red") blood then returns to the left heart, via the pulmonary veins, and is pumped through the aorta to the rest of the body, including the heart muscle itself. This is the systemic circulation part of blood flow, the other loop of an interconnected normal cardio-pulmonary system. With d-TGA, certain major blood vessels are connected improperly, so oxygen-poor blood from the right heart is pumped immediately through the aorta and circulated to the body and the heart itself, bypassing the lungs altogether, while the left heart pumps oxygen-rich blood continuously back into the lungs through the pulmonary artery. This is a life-threatening situation due to the resultant low oxygen levels throughout the body.
