Abstract 14559: Venous Flow Dynamics Rather Than Venous Pressure is Important for the Development of Liver Fibrosis After Atriopulmonary Fontan Procedure
Background: Elevated venous pressure is thought to play a pivotal role in the development of liver fibrosis/dysfunction, an important complication after Fontan surgery, particularly that for the atriopulmonary connection (APC). We hypothesized that right atrial volume (RAv) rather than RA pressure (RAp) is important for the progression of liver fibrosis.
Methods: We studied 51 consecutive APC-Fontan patients who underwent cardiac catheterization (median postoperative period: 14 years). RAv was calculated by a biplane Simpson’s method using RA-graphy. Based on the median RAp (mmHg) and RAv (mL/m2), we divided patients into 4 groups: Group A (n = 17), RAp < 13 and RAv < 100; Group B (n = 17), RAp > 13 and RAv < 100; Group C (n = 10), RAp < 13 and RAv > 100; and Group D (n = 7), RAp > 13 and RAv > 100. Abdominal echographic findings and laboratory data for liver function and liver fibrosis were compared among the 4 groups.
Results: There was no significant difference in the postoperative periods among the groups. Echographic diagnosis of liver fibrosis was made in 18, 42, 90, and 86% of Group A, B, C, and D, respectively (P = 0.02, Group A vs. the other groups). Importantly, the incidence of liver fibrosis was significantly higher in Groups C and D than in Group B (P = 0.04), suggesting the pathophysiologic importance of RAv over RAp. In addition, abnormal levels of hyaluronic acid (> 50 ng/mL), a marker of liver fibrosis, were observed more frequently in the high-RAv groups than in the low-RAv groups (29, 47, 70, and 86% in Group A, B, C, and D, respectively, P < 0.05 for Groups A or B vs. Groups C and D). Multivariate analysis determined that only RAv, not RAp, was a significant predictor of the presence of liver fibrosis (P < 0.01).
Conclusion: The present results indicate the importance of venous flow stagnation rather than high venous pressure for the development of post-Fontan hepatic complication. The results suggest that 1) Fontan conversion procedure prior to RA dilation is beneficial to prevent liver fibrosis in APC-Fontan patients, and that 2) advanced techniques that enable the prediction of venous flow dynamics and venous pressure should be incorporated in pre-Fontan evaluation to achieve Fontan completion with better outcomes even in other types of Fontan procedure.
- © 2013 by American Heart Association, Inc.