CPT® Code 33645

Direct or patch closure of a sinus venosus type defect is a surgical procedure aimed at correcting a specific type of atrial septal defect known as sinus venosus atrial septal defect (SVASD). This defect is characterized by an abnormal opening in the upper part of the atrial septum, which separates the right and left atria of the heart. The most prevalent form of this defect is located near the superior vena cava, often accompanied by anomalous pulmonary venous drainage, where the right upper pulmonary vein drains into the superior vena cava instead of the left atrium. There are variations of this defect, including one that occurs at the junction of the right atrium and inferior vena cava, which may involve the right lower pulmonary vein draining into the inferior vena cava. The least common variant is situated posterior to the fossa ovalis and does not involve the major venous structures. The surgical approach typically involves a median sternotomy or an upper hemisternotomy to access the heart. Once the heart is accessed, cardiopulmonary bypass is established to maintain circulation while the heart is temporarily stopped. The procedure involves incising the right atrium to expose the defect, followed by either direct suturing for smaller defects or the use of a patch graft for larger defects that involve the vena cava. This intervention not only closes the septal defect but also corrects any associated anomalous pulmonary venous drainage, thereby restoring normal blood flow within the heart.