Outcomes of Current Surgical Strategy for Achieving Optimal Fontan Haemodynamics in Patients With Right Isomerism

Cardiac malformations are a major component of heterotaxy syndrome that result in significant mortality and morbidity, especially in patients with right isomerism (RI) and functional single ventricle (FSV). Over the past 20 years, we have adopted a surgical strategy at initial palliation for achieving optimal Fontan haemodynamics. Here, we aimed to evaluate the mortality and morbidity associated with the current surgical strategy and to identify predictive risk factors for mortality.

A retrospective review of medical records was performed on 91 consecutive patients with RI and FSV who underwent initial palliation at Mt. Fuji Shizuoka Children's Hospital between 2000 and 2023.

The estimated survival rates of the overall cohort at 1 and 10 years were 78.0% and 66.2%, respectively. The completion rate of the Fontan procedure excluding waiting cases was 57.1% (52/84). In multivariable analysis, pulmonary atresia (hazard ratio 5.44 [95% confidence interval, 1.57-22.2]) and the grade of common atrioventricular valve regurgitation before initial palliation (hazard ratio 2.17 [95% confidence interval, 1.07-4.76]) were predictors of mortality. Haemodynamic data from pre-Fontan cardiac catheterization were available for 52 patients. A comparison with a concurrently studied cohort of patients with non-RI and FSV (n = 253) revealed no significant differences in any of the measured haemodynamic variables.

Surgical intervention in patients with RI and FSV remains challenging. Findings from the pre-Fontan catheter studies suggest that our current surgical strategy may provide a safe and effective pathway towards Fontan candidacy.