Contemporary outcomes after the Fontan procedure: a Pediatric Heart Network multicenter study

Abstract

Objectives: We characterized a large cohort of children who had a Fontan procedure, with measures of functional health status, ventricular size and function, exercise capacity, heart rhythm, and brain natriuretic peptide (BNP).

Background: The characteristics of contemporary Fontan survivors are not well described.

Methods: We enrolled 546 children (age 6 to 18 years, mean 11.9 years) and compared them within pre-specified anatomic and procedure subgroups. History and outcome measures were obtained within a 3-month period.

Results: Predominant ventricular morphology was 49% left ventricular (LV), 34% right ventricular (RV), and 19% mixed. Ejection fraction (EF) was normal for 73% of subjects; diastolic function grade was normal for 28%. Child Health Questionnaire mean summary scores were lower than for control subjects; however, over 80% of subjects were in the normal range. Brain natriuretic peptide concentration ranged from <4 to 652 pg/ml (median 13 pg/ml). Mean percent predicted peak O2 consumption was 65% and decreased with age. Ejection fraction and EF Z score were lowest, and semilunar and atrioventricular (AV) valve regurgitation were more prevalent in the RV subgroup. Older age at Fontan was associated with more severe AV valve regurgitation. Most outcomes were not associated with a superior cavopulmonary connection before Fontan.

Conclusions: Measures of ventricular systolic function and functional health status, although lower on average in the cohort compared with control subjects, were in the majority of subjects within 2 standard deviations of the mean for control subjects. Right ventricular morphology was associated with poorer ventricular and valvular function. Effective strategies to preserve ventricular and valvular function, particularly for patients with RV morphology, are needed.

Figure 1. CHQ-PF Summary Scores

The distribution of CHQ-PF Physical and Psychosocial Summary Scores from 543 children enrolled in the Pediatric Heart Network Fontan Cross-Sectional Study. The bar represents the 95% confidence interval around the historical mean score for healthy children.

Figure 2. Mass/EDV Ratio and Diastolic Function

Histograms of echocardiographic mass to EDV ratio z score and measures of diastolic function assessed from tissue Doppler techniques, by ventricular morphology. Shaded regions indicate the 95% confidence interval for normal children aged 6 to 18 years old (19).