Abstract 10993: Age at Fontan Procedure impacts Exercise Performance in Adolescents: Results from Pediatric Heart Network Multicenter Study
Background: Majority of the single ventricle patients undergo Fontan procedure in a staged manner. However, optimal timing of Fontan completion after an intermediate staging surgery is controversial. Therefore, we investigated the long-term impact of age at Fontan completion on the exercise performance in adolescents.
Methods: We analyzed NIH/NHLBI Pediatric Heart Network Fontan Cross-Sectional Study dataset consisting of children and adolescents age 6-18 years recruited into the study in 2003-04. Associations between demographic, disease related and procedure-related variables, including age at Fontan procedure, and risk of not achieving Ventilatory anerobic threshold (VAT) on exercise testing were evaluated using unconditional logistic regression. Multivariate linear regression techniques were used to evaluate association of age at Fontan procedure with percent predicted VO2 maximum, percent predicted maximum O2 pulse, and heart rate reserve in patients who achieved VAT.
Results: Retrospective data on 405 patients who had undergone only one Fontan operation and ramp cycle ergometry were analyzed. 72% of patients had prior intermediate surgery. Mean age at Fontan completion and exercise testing was 3.4±2 and 12.4±3.2 years respectively; 58.5% were males. 312 patients reached VAT suggesting adequate cardiopulmonary effort. In patients who reached VAT, each year delay in age at Fontan completion was associated with a decline of 1.5 (95% CI -2.5 to -0.5) points in percent predicted VO2 maximum after adjusting for demographic, disease related and surgical characteristics. Similarly, each year delay in age at Fontan completion was associated with a decline of 4.1 (95% CI -6.0 to -2.1) beats/min in heart rate reserve. Although age at first volume-unloading surgery (i.e. age at intermediate surgery or age at Fontan procedure if Fontan was done as a single staged procedure) was not associated with any decline in the exercise performance measures in patients who achieved VAT, older age at first unloading surgery was associated with higher risk of not achieving VAT on exercise testing (OR 1.3, 95% CI 1.1-1.6).
Conclusions: Patients who undergo Fontan completion at a younger age have better exercise performance than those who receive delayed surgery.
- © 2012 by American Heart Association, Inc.