Cardiac troponin I in congenital heart defects with pressure or volume overload.

ABSTRACT

OBJECTIVE: To evaluate the prevalence of cardiac troponin I (cTnI) and autoantibodies to cTn in children with congenital heart defects with volume or pressure overload fulfilling the criteria for treatment, and in healthy children. DESIGN: The study groups comprised 78 children with volume overload caused by an atrial septal defect or a patent ductus arteriosus, and 60 children with pressure overload caused by coarctation of the aorta or stenosis of the aortic or the pulmonary valve, and 74 healthy controls. Serum levels of natriuretic peptides, cTnI, and autoantibodies to cTn were analyzed at baseline, prior to treatment and in 64 patients 6 months after treatment. RESULTS: At baseline, one child with volume overload, 12 children with pressure overload, and one healthy control had positive cTnI. Further analysis of the pressure overload subgroup revealed that the children with positive cTnI were younger than those with negative cTnI, and had higher levels of natriuretic peptides. The pressure gradient at the coarctation site or stenotic valve was higher in those with positive TnI. Six months after treatment, 63 of 64 children examined were cTnI negative. CONCLUSIONS: The cTnI release is more frequently associated with pressure than volume overload which resolves after treatment in most children.