LAUSR

We aimed to evaluate and compare the physical fitness of children with different severity of the cardiac defect with their healthy peers. We included 182 children after cooperation for congenital heart disease (CHD) and 129 healthy children as controls, 6-18years old, who performed a complete cardiopulmonary exercise test (CPET) in a cross-sectional observational study. The CHD patients were further subdivided into three subgroups according to diagnostic characteristics and surgical methods: simple CHD group (SCHD), complex CHD group (CCHD)and total cavopulmonary connection group (TCPC). Physical fitness was compared between groups using generalized linear model and multiple linear regression analysis. In comparison with age and gender adjusted healthy controls, children in SCHD, CCHD and TCPC subgroups had accordingly graded down values of peak oxygen consumption (VO2max: 44.86±5.41 vs. 39.91±5.59 vs. 36.95±5.92 vs. 32.04±5.38 ml/kg/min, P<0.05) and %predicted VO2max (1.01±0.14 vs. 0.91±0.13 vs. 0.83±0.15 vs. 0.72±0.13, P<0.05) for each group. The proportion of %predicted VO2max above 80% in the CHD and the control group were 60.4% and 96.1% (P<0.001). The VO2max decreased by 0.98ml/kg/min per year in CHD children, and the corresponding % predicted reference diminished by 2.0%. Children with TCPC had the highest mean decrease of VO2max and %predicted VO2max per year of age (1.23ml/kg/min, corresponding 3.0%). Although the mean overall physical fitness of children with simple and complex defect after biventricular correction were significantly different from healthy population, they were close to normal (>80%predicted VO2max). However, TCPC group had much lower exercise capacity.