Off-Pump Obstructed Extracardiac Fontan Conduit Bypass in a Single Ventricle with Dextrocardia

The patient was an 18-year-old male who presented with fatigue and exercise intolerance. He was born with dextrocardia and a functional single ventricle secondary to severely unbalanced complete atrioventricular septal defect with transposition of the great arteries and pulmonary atresia. He had undergone all three stages of palliation as a neonate, at two years, and at three years of age, respectively. 

Preoperative cardiac catheterization revealed a small, calcified extracardiac Fontan conduit, which appeared obstructive and potentially causing his symptoms. 

The decision was made to proceed with the replacement of his Fontan conduit. 

Through a fourth sternotomy and after the initial mediastinal dissection, the previously placed Fontan conduit was identified and partially dissected. However, it was quite adherent to the left phrenic nerve and was inserted directly opposite the left cavopulmonary anastomosis. Therefore, the surgeons decided to create a new extracardiac conduit directed to the right pulmonary artery instead to minimize energy loss through the old Fontan design. This approach appeared feasible without the need for cardiopulmonary bypass. 

The junction of the inferior vena cava and the old conduit junction were dissected, and a side-biting clamp was placed. A new 20 mm externally reinforced polytetrafluoroethylene (PTFE) graft was then sewn to the inferior vena caval/old conduit connection using running 5/0 polypropylene suture. The clamp was then removed, and the anastomosis was de-aired. Due to the dextrocardia, the surgeons routed the new graft posterior to the systemic ventricle, adjusting its length accordingly. The distal anastomosis was then made in a similar fashion to the right pulmonary artery. This created an additional route from the inferior vena cava to the pulmonary circulation that should be more energy efficient. The remaining part of the procedure and closure were completed in a routine fashion. 

The patient was extubated in the operating room, and his postoperative course was uneventful. He was discharged on the ninth postoperative day and continued to do well at the two year follow-up. Follow-up computed tomography with 3-D reconstruction showed that both extracardiac Fontan conduits were widely patent. 

References

1. Said S, Marey G. Off-pump extracardiac Fontan completion: Surgical technique and pitfalls. Multimed Man Cardiothorac Surg. 2021;2021:10.1510/mmcts.2021.004. Published 2021 Jan 28. doi:10.1510/mmcts.2021.004
2. Shiraishi S, Uemura H, Kagisaki K, Koh M, Yagihara T, Kitamura S. The off-pump Fontan procedure by simply cross-clamping the inferior caval vein. Ann Thorac Surg. 2005;79(6):2083-2088. doi:10.1016/j.athoracsur.2004.11.056

Disclaimer

The information and views presented on CTSNet.org represent the views of the authors and contributors of the material and not of CTSNet. Please review our full disclaimer page here.