Anthropometric measures after Fontan procedure: implications for suboptimal functional outcome.

ABSTRACT

BACKGROUND: Abnormal height and adiposity are observed after the Fontan operation. These abnormalities may be associated with worse functional outcome. METHODS: We analyzed data from the National Heart, Lung, and Blood Institute Pediatric Heart Network cross-sectional study of Fontan patients. Groups were defined by height (z-score<-1.5 or≥-1.5) and body mass index (body mass index [BMI] z-score<-1.5 or -1.5 to 1.5 or≥1.5). Associations of anthropometric measures with measurements from clinical testing (exercise, echocardiography, magnetic resonance imaging) were determined adjusting for demographics, anatomy, and pre-Fontan status. Relationships between anthropometric measures and functional health status (FHS) were assessed using the Child Health Questionnaire. RESULTS: Mean age of the cohort (n=544) was 11.9±3.4 years. Lower height-z patients (n=124, 23%) were more likely to have pre-Fontan atrioventricular valve regurgitation (P=.029), as well as orthopedic and developmental problems (both P<.001). Lower height-z patients also had lower physical and psychosocial FHS summary scores (both P<.01). Higher BMI-z patients (n=45, 8%) and lower BMI-z patients (n=53, 10%) did not have worse FHS compared to midrange BMI-z patients (n=446, 82%). However, higher BMI-z patients had higher ventricular mass-to-volume ratio (P=.03) and lower % predicted maximum work (P=.004) compared to midrange and lower BMI-z patients. CONCLUSIONS: Abnormal anthropometry is common in Fontan patients. Shorter stature is associated with poorer FHS and non-cardiac problems. Increased adiposity is associated with more ventricular hypertrophy and poorer exercise performance, which may have significant long-term implications in this at-risk population.