Prognostic value of pre- and postoperative cardiac troponin I measurement in children having cardiac surgery

The objective of this study was to determine if perioperative elevation of cardiac troponin I (cTnI) predicts mortality in infants and children after surgical correction of congenital heart defects. One hundred infants and ch ildren having open heart surgery were studied. Blood samples for cTnI analy sis were collected before cardiopulmonary bypass (CPB) and at 4, 8, 12, and 24 h after initiation of CPB. Demographic information, cardiac defect, rep air performed, duration of CPB, complications, and outcome were recorded. C ardiac defects were categorized as atrial septal defect (ASD), ventricular septal defect (VSD), hypoplastic left heart syndrome (HLHS), complex, and " other." Baseline cTnI was significantly lower in survivors (mean 0.42 ng/ml , median 0.35 ng/ml) than in nonsurvivors (mean 1.89, median 1.30), p = 0.0 001. Baseline cTnI was significantly higher in the HLHS group (mean 1.47, m edian 1.10) than in all other subgroups(mean 0.62, median 0.35), p less tha n or equal to 0.009. There were no significant differences between survivor s and nonsurvivors at the remaining sampling times. Children who died from cardiac failure (n = 2) were more likely to have 4 h cTnI >125 ng/ml compar ed to survivors (2 of 90). Within cardiac defect subgroups, 4 h cTnI was si gnificantly higher in the complex group (mean = 53.51, median = 32.30) than in the ASD (mean = 23.84, median = 19.85) and other (mean = 21.59, median 21.50) subgroups. Perioperative measurement of cTnI identifies children wit hin specific cardiac defect subgroups at risk of mortality after cardiac su rgery. We speculate that detection of myocardial injury may decrease mortal ity and morbidity in children with complicated congenital cardiac lesions b y leading to improvements in perioperative management.