Zheng H, et al. - In this retrospective study, the temporal measurements of N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels at 1, 3, 6, 12, and 18 months after surgery was carried out over a period of 18 months in 136 children with a median age of 7 months who had underwent cardiac surgery for tetralogy of Fallot (TOF). Researchers also investigated the possible impact of commonly used pharmaceuticals (ie, spironolactone and digoxin) on the normalization pattern. The definition of normalization of NT-proBNP was an NT-proBNP level ≤ 250 pg/ml. The estimated rate of normalization was 24.2% per 100 person-days, and a median normalization time of 517 days was seen in Kaplan-Meier survival analysis. A significantly higher readmission rate was observed among children whose NT-proBNP level did not normalize vs those whose NT-proBNP level did normalize. Overall, NT-proBNP normalization following cardiac surgery for TOF was recognized as a lengthy process. Failure in recovery and hospital readmission could take place due to irregular use of spironolactone, while regular users of spironolactone, either alone or in combination with digoxin, had distinctly faster recovery trajectories for measures of NT-proBNP.