Trajectories of postoperative serum troponin concentrations following pediatric heart transplantation

Abstract

IntroductionTroponin is a readily measured serum biomarker of myocardial injury and death, but has not been well studied after pediatric heart transplants. The objective of this analysis is to describe the distribution and clinical determinants of serum troponin measured in the first week after pediatric heart transplantation. MethodsWe included all patients who underwent heart transplantation at Seattle Children’s Hospital between January 1, 2012 and December 31, 2016. During this period, serum Troponin-I (TnI) was measured daily in the first week after heart transplant. We described the distribution of serum TnT collected in this period. We examined the relationship between peak TnI with known pre- peri-operative risk factors for myocardial injury including etiology of heart failure, ischemia time, and donor to recipient characteristics. Logistic regression models were used to test the association between peak TnI with incidence of death or rejection and formation of donor specific antibodies within 1 year. Adjusted models included age, HF etiology, crossmatch status, and panel reactive antibodies. ResultsDuring the study period, 86 transplants were performed on 83 unique individuals. Serum TnI peaked at a median of 0.9 days after transplantation. In adjusted models, higher peak TnI was associated with death and/or rejection within 1-year post-transplant (Odds Ratio [95% confidence interval]: 1.10 [1.02, 1.19]). Higher peak TnI was not associated with de-novo DSA formation in adjusted models (OR [95%CI]: 1.01 [0.94, 1.09]). Post-transplant length of stay in the intensive care unit was positively correlated with peak TnI (r=0.36, p<0.001). ConclusionsThis study provides a description of serum TnI in the first week after pediatric heart transplant; a population for whom existing data is sparse. Post-transplant TnI reflects pre- and peri-operative factors such as ischemia time. This suggests TnI may have utility as a readily measurable biomarker of transplant-related myocardial injury. Our results serve as a basis to test the prognostic significance of higher post-transplant TnI in future studies.