20 years of experience with the Fontan procedure: Risk factors for adverse outcomes

The Fontan procedure and the management of patients with univentricular physiology have undergone significant evolution over the past five decades. However, the long-term outcomes of these patients remain not fully understood. This study aimed to evaluate the early and long-term outcomes of patients undergoing the Fontan procedure and to identify risk factors associated with adverse clinical events.

Patients who underwent the Fontan procedure between 2004 and 2023 were included in this study. Multivariable logistic regression analysis was employed to assess risk factors for early mortality, while a Cox proportional hazards regression model was used to evaluate predictors of long-term Fontan failure.

A total of 400 patients were included, with a male predominance (67.3%). Median age at the time of the Fontan procedure was 5.8 years (interquartile range: 4.1-11.0 years). The distribution of ventricular morphology was as follows: dominant right ventricle (33%), dominant left ventricle (35.75%), and two well-developed ventricles (28.75%). The early mortality rate was 5.5%. The overall survival rates at 5-, 10-, and 15-years post-Fontan surgery were 97.5%, 92.6%, and 90.0%, respectively. Multivariable analysis identified asplenia (odds ratio [OR], 10.2; 95% confidence interval [CI], 2.8-36.4; p<0.01), single-stage total cavopulmonary connection (OR, 5.3; 95% CI, 1.7-16.8; p<0.01), and prolonged cardiopulmonary bypass time (OR, 1.0; 95% CI, 1.0-1.0; p<0.01) as significant predictors of early mortality. Cox regression analysis demonstrated that heterotaxy (hazard ratio [HR], 3.5; 95% CI, 1.4-8.7; p<0.01) was an independent risk factor for late Fontan failure.

The staged Fontan strategy was associated with reduced early mortality but did not confer significant benefits on long-term outcomes. Patients with heterotaxy were at an increased risk of late Fontan failure, highlighting the need for tailored management strategies in this high-risk population.