Balloon atrial septostomy

Balloon atrial septostomy

Balloon atrial septostomy is the classic bail out procedure for the deeply cyanosed and acidotic newborn with d-transposition of great arteries and poor admixture. Since the systemic and pulmonary circulations are in parallel in d-TGA, it is urgent to provide good mixing at the atrial level which is the most preferred site, at the earliest. This where the balloon atrial septostomy comes in as a life saving option, which buys time for corrective surgery.

Balloon atrial septostomy was initially described in 1966 by Rashkind and Miller. In the immediate neonatal period the approach is often through the umbilical vein, though femoral vein is an option later on. Balloon septostomy catheter is introduced into the left atrium under fluoroscopy or sometimes under echocardiographic guidance. Echocardiography is more often used to guide the proper position of the interatrial septum rather than as a total guidance in the absence of fluoroscopy. The balloon at the tip of the catheter is inflated and abruptly pulled back into the right atrium tearing the inter atrial septum.

A good defect will improve the mixing and consequently the systemic oxygen saturation as more deoxygenated blood reaches the lung for oxygenation, unlike the pure d-TGA in which hardly any portion of the systemic venous drainage is carried to the lungs for oxygenation. Adequacy of the septal tear is indicated by only minimal gradient across the interatrial septum after the procedure. Beyond the neonatal period, septum becomes thick and difficult to tear by simple balloon atrial septostomy when a blade atrial septostomy may be needed. This procedure utilizes a catheter mounted blade to make an incision in the interatrial septum.