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Updated: Aug 17, 2026
Echocardiographic Evaluation of Atrial Communications before Transcatheter Closure
Published on: February 8, 2022
Hemodynamic evaluation of Fontan operation in tricuspid atresia
Insights
Hemodynamic studies after modified Fontan operations show improved arterial saturation. However, elevated right atrial pressure and residual hypoxemia persist in some patients, with one death linked to valve complications.
Area of Science:
- Cardiology
- Pediatric Cardiac Surgery
- Hemodynamics
Background:
- The modified Fontan operation is a palliative procedure for complex congenital heart disease.
- Long-term hemodynamic assessment is crucial for evaluating the success of this surgery.
Purpose of the Study:
- To assess the hemodynamic status and clinical outcomes of patients following a modified Fontan operation.
- To identify factors contributing to residual hypoxemia and elevated atrial pressures.
Main Methods:
- Hemodynamic studies were conducted on six patients 2-34 months post-modified Fontan operation.
- Cardiac catheterization was performed, with some patients undergoing repeat studies.
- Atrial transport function, rhythm, and pressure gradients were evaluated.
Main Results:
- Average arterial saturation improved by 13% post-surgery (92%).
- Four patients were in sinus rhythm, two in junctional rhythm; all had good atrial transport.
- Elevated right atrial pressure (average 17 mm Hg) and RA-LPA gradients were observed in some patients.
Conclusions:
- Modified Fontan operation improves arterial oxygen saturation but can lead to persistent hemodynamic challenges.
- Residual hypoxemia is linked to pulmonary vein desaturation and atrial shunting.
- A patient died due to complications from porcine valve failure, highlighting potential long-term risks.
Abstract:
Six patients underwent hemodynamic studies at 2 to 34 months (mean 15 months) following a modified Fontan operation. Only one patient had a valve at the inferior vena cava (IVC)-right atrium (RA) junction. Average age at surgery was 12 years (range 5-26 years). Three patients were catheterized twice. Postoperative studies showed four patients to be in sinus rhythm and two in junctional rhythm. Two patients had a RA-left pulmonary artery (LPA) gradient across the conduit of 1.5-10 mm Hg. The RA pressure was elevated an average of 17 mm Hg (10-34). All patients showed good atrial transport function regardless of their rhythm. The average arterial saturation was 92% (87%-97%), which was an improvement of 13% over preoperative values. Residual hypoxemia was due to pulmonary vein desaturation and to atrial right-to-left shunting early after surgery and to atrial right-to-left shunt alone, later. Death followed re-operation for removal of the porcine valves in the patient with two valves inserted. Macroscopically, both valves were found to have fibrous tissue ingrowth that had fixed them in a semi-open position.
