CPT® Code 33770

Repair of transposition of the great arteries with ventricular septal defect and subpulmonary stenosis; without surgical enlargement of ventricular septal defect

The procedure described by CPT® Code 33770 involves the surgical repair of a congenital heart defect known as transposition of the great arteries (TGA), which is characterized by an abnormal arrangement of the major blood vessels. In a normal heart, the aorta arises from the left ventricle, while the pulmonary arteries originate from the right ventricle. However, in TGA, the aorta is connected to the right ventricle, and the pulmonary arteries are connected to the left ventricle. This misconfiguration results in a situation where oxygen-poor blood is circulated back to the body without passing through the lungs for oxygenation, while oxygen-rich blood returns to the lungs instead of being delivered to the body. The procedure specifically addresses cases where TGA is complicated by a ventricular septal defect (VSD) and subpulmonary stenosis. A VSD is an opening in the ventricular septum, the wall dividing the left and right ventricles, which allows for the mixing of oxygen-rich and oxygen-poor blood. Subpulmonary stenosis refers to a narrowing of the main pulmonary artery just below the pulmonary valve, which can obstruct blood flow from the right ventricle to the lungs. In this surgical intervention, the repair is performed without enlarging the VSD, distinguishing it from similar procedures that may involve such enlargement. The complexity of the operation necessitates a tailored approach for each patient, as the specific anatomical and physiological conditions can vary significantly. The procedure typically requires access to the heart through a median sternotomy or thoracotomy, and involves several critical steps to ensure proper blood flow and heart function post-surgery.