CPT® Code 33617

1. Indications

The modified Fontan procedure, represented by CPT® Code 33617, is indicated for patients with complex cardiac anomalies, particularly those with a single ventricle heart condition. This condition may manifest in various forms, including:

• Single Ventricle Heart Defect A congenital heart defect where one of the ventricles is either absent or underdeveloped, leading to inadequate blood circulation.
• Hypoplastic Left Heart Syndrome A specific type of single ventricle defect where the left side of the heart is critically underdeveloped.
• Tricuspid Atresia A condition where the tricuspid valve is absent or malformed, preventing proper blood flow from the right atrium to the right ventricle.
• Other Complex Cardiac Anomalies Various other congenital heart defects that result in a single functional ventricle.

2. Procedure

The modified Fontan procedure involves several critical steps to effectively repair the complex cardiac anomalies associated with a single ventricle heart. The procedure begins with a median sternotomy, which is a surgical incision made along the sternum to provide access to the heart. Following this, cardiopulmonary bypass is initiated, allowing the surgeon to temporarily take over the function of the heart and lungs, ensuring that blood circulation is maintained during the operation.

Next, the surgeon makes two incisions in the right atrium: one incision is located near the atrioventricular groove, while the other is a trap-door incision made in the superior aspect of the right atrium. These incisions are crucial for accessing the heart's internal structures and facilitating the subsequent steps of the procedure.

After accessing the right atrium, the main pulmonary artery is incised inferiorly. This incision is extended toward the first right hilar branch on one side and the left pulmonary artery on the other side, allowing for the necessary modifications to the pulmonary artery structure.

Following the incision of the pulmonary artery, the trap-door incision in the right atrium is sutured to the pulmonary artery incision. This step is essential for creating a connection between the right atrium and the pulmonary artery, which is vital for directing blood flow appropriately.

Finally, a lateral tunnel is created in the right atrium using a synthetic tube graft. This graft serves to direct blood flow from both the inferior and superior vena cavae into the pulmonary arteries, thereby enhancing the efficiency of the single ventricle in pumping blood to the lungs for oxygenation.

3. Post-Procedure

Post-procedure care following the modified Fontan procedure is critical for patient recovery and monitoring. Patients typically require close observation in a cardiac intensive care unit to manage any potential complications. Expected recovery includes monitoring for signs of heart function improvement, as well as managing fluid balance and ensuring adequate oxygenation. Follow-up appointments are essential to assess the long-term outcomes of the procedure, including the function of the single ventricle and the effectiveness of the newly created lateral tunnel. Additional considerations may include ongoing cardiac evaluations and potential interventions as the patient grows and develops.