Linear growth in relation to the circulating concentration of insulin-like growth factor-I and free thyroxine in infants and children with congenital cyanotic heart disease before vs. after surgical intervention.

This prospective controlled study recorded the anthropometric data and measured the circulating insulin-like growth factor-I (IGF-I) in 16 children with congenital cyanotic heart disease before and a year after surgical intervention. At presentation patients were significantly shorter [length SD scores (LSDS) = -2.44 +/- 1.31], vs. controls (LSDS = -0.25 +/- 0.18). After surgical treatment the LSDS and growth velocity SD scores (GVSDS) increased significantly to (-) 0.25 +/- 0.95 and 3.7 +/- 2.1, respectively. IGF-I increased from 45.7 +/- 26.3 ng ml(-1) to 67.7 +/- 16.4 ng ml(-1). The GVSDS after treatment was correlated with the body mass index (BMI) (r = 0.339, p < 0.05) and negatively with the LSDS before surgery (r = -0.461, p < 0.05). The percentage increase of IGF-I after operation was correlated significantly with the BMI after surgical intervention (r = 0.82, p < 0.001). It appears that the postoperative growth spurt in infants with cyanotic congenital heart disease (CHD) is mediated through activation of the GH/IGF-I system and improved nutrition.