Transplant coronary artery disease in pediatric heart transplant recipients

Background: Transplant coronary artery disease (TxCAD) contributes to a lar ge percentage of late morbidity and mortality among adult heart transplant recipients. Intracoronary ultrasound (ICUS) is a sensitive tool in the diag nosis of TxCAD in adult patients and has allowed analysis of factors contri buting to disease development. Experience with ICUS in pediatrics, however, has been limited. By using ICUS we sought to determine the overall prevale nce of TxCAD in pediatrics and to characterize factors associated with its development in this population. Methods: Eighty-six studies were performed in 51 pediatric patients a media n of 3.4 years after heart transplantation. Evaluation included angiography and ICUS in 83 and angiography alone in 3 studies. Donor and recipient cha racteristics were obtained. The ICUS images were analyzed for intimal thick ening and compared with coronary angiograms. The presence of any intimal th ickening on ICUS was considered TxCAD. An intimal index and point of maxima l intimal thickening (MIT) were measured. Vessel disease was graded 0 to 4 based on these results. Results: Four patients had evidence of vasculopathy by angiography, whereas 32 patients (63%) had evidence of intimal proliferation by ICUS. Grade 3 o r greater disease was present in 19 (37%) patients. A positive correlation was found when comparing time from transplant with intimal index and MIT (p < 0.001). No other factors were found to predict the development of diseas e. The overall prevalence of disease was 74% in patients studied at least 5 years after transplant. Conclusions: Intracoronary ultrasound can be performed safely in pediatric patients. Transplant coronary artery disease is common in infants and child ren after heart transplantation, although its prevalence appears to be less than in adult recipients at similar time intervals. We found no factor oth er than time from transplant was associated with development of disease.