Impact of fenestration patency on long-term Fontan outcomes

Abstract Objectives Routine creation of a fenestration during Fontan completion is our policy to stabilize early circulation. This study evaluated its validity by examining the impact of fenestration patency at 1 year on long-term outcomes. Methods Among 112 patients who underwent fenestrated total cavopulmonary connection at four institutions, 105 with one-year catheterization and ≥3 years of follow-up were analyzed. Patients were classified by fenestration status at 1 year: patent (Group F, n = 43) and closed (Group C, n = 62). Preoperative and one-year catheter data and long-term complications—Fontan-associated liver disease, protein-losing enteropathy, and catheter interventions excluding veno-venous collaterals—were compared. Results The median age at Fontan was 23 months (IQR: 15–33). Preoperative hemodynamics showed no differences between the groups. At postoperative 1-year, systemic ventricular end-diastolic pressure was higher in Group F (F: 8 5–9 vs C: 6 5–8 mmHg, P = 0.007). Protein-losing enteropathy was significantly more common in the Group C (F: 5.0% vs. C: 27.0%, P = 0.038). In contrast, there was no significant difference in the cumulative incidence of Fontan-associated liver disease between the two groups (F: 12.5% vs. C: 9.7%, P = 0.69). Conclusion Although patent fenestration was associated with an increased systemic ventricular end-diastolic pressure at one year postoperatively, it may improve long-term outcomes including protein-losing enteropathy. As predicting eventual fenestration patency from preoperative data is difficult, our policy of routine fenestration creation appears to be a valid strategy.