IGFBP7 and congenital heart disease: In our study population, baseline [TIMP-2]•[IGFBP7] levels were not elevated in patients with either immature kidneys (<2 years) or venous congestion resulting from congenital heart disease (data not shown), suggesting that [TIMP-2]•[IGFBP7] serves as a marker of acute injury to the kidney after cardiac surgery with CPB.