Preliminary clinical experience with a bifurcated Y-graft Fontan procedure--a feasibility study

Objective: Optimizing flow and diminishing power loss in the Fontan circuit can improve hemodynamic efficiency, potentially improving the long-term outcomes. Computerized modeling has predicted improved energetics with a Y-graft Fontan.

Methods: From August to December 2010, 6 consecutive children underwent completion Fontan (n=3) or Fontan revision (n=3) using a bifurcated polytetrafluoroethylene Y-graft (18×9×9 mm in 2, 20×10×10 mm in 4) connecting the inferior vena cava to the right and left pulmonary arteries with separate graft limbs. The patents underwent magnetic resonance imaging (n=5) or computed tomography (n=1). Computational fluid dynamics assessed Fontan hemodynamics, power loss, and inferior vena cava flow splits to the branch pulmonary arteries. The clinical parameters were compared with those from 12 patients immediately preceding the present series who had undergone a lateral Fontan procedure.

Results: Despite longer crossclamp and bypass times (not statistically significant), the Y-graft Fontan patients had postoperative courses similar to those of the conventional Fontan patients. Other than 2 early readmissions for pleural effusions managed with diuretics, at 6 to 12 months of follow-up (mean, 8 months), all 6 patients had done well. Postoperative flow modeling demonstrated a balanced distribution of inferior vena cava flow to both pulmonary arteries with minimal flow disturbance. Improvements in hemodynamics and efficiency were noted when the Y-graft branches were anastomosed distally and aligned tangentially with the branch pulmonary arteries.

Conclusions: The present preliminary surgical experience has demonstrated the clinical feasibility of the bifurcated Y-graft Fontan. Computational fluid dynamics showed acceptable hemodynamics with low calculated power losses and a balanced distribution of inferior vena cava flow to the pulmonary arteries as long as the branch grafts were anastomosed distally.