CPT® Code 93585

Add-On Code

Venography for congenital heart defect(s), including catheter placement, and radiological supervision and interpretation; azygos/hemiazygos venous system (List separately in addition to code for primary procedure)

This procedure, identified by CPT® Code 93585, involves performing a venography specifically for congenital heart defects, which includes the placement of a catheter and the necessary radiological supervision and interpretation. The focus of this venography is on the azygos and hemiazygos venous systems, which are critical components in the venous drainage of the thoracic cavity. This service is typically conducted as an add-on to a primary diagnostic cardiac catheterization, particularly in pediatric patients who present with congenital heart defects. A common clinical scenario for this procedure is seen in infants diagnosed with cardiac heterotaxy, a condition where the heart is positioned abnormally within the chest and is often associated with various complex anatomical anomalies. The azygos vein, which ascends along the right side of the posterior mediastinum, plays a vital role in returning deoxygenated blood from the lower body to the heart. It originates from the inferior vena cava (IVC) at a level comparable to the renal veins and ultimately drains into the superior vena cava (SVC), facilitating the return of blood to the right atrium. The hemiazygos vein serves as a tributary that collects blood from the left mediastinum and the lower left esophagus, crossing over to the right side at approximately the T9 vertebral level to join the azygos vein. During the procedure, a guide catheter is inserted through a venous access sheath and advanced over a guidewire into the inferior vena cava as part of a diagnostic right and left heart catheterization. Once positioned, contrast material is injected to visualize the venous structures, and images are captured to evaluate the anatomy and drainage patterns of the azygos and hemiazygos venous systems. If an anomalous inferior vena cava is identified, the guidewire is maneuvered into this additional vessel, and the catheter is repositioned accordingly to perform the venography, ensuring a comprehensive assessment of the venous drainage in the context of the congenital heart defect.