The medium-term findings in coronary arteries by intravascular ultrasound in infants and children after heart transplantation

OBJECTIVES The study purposes were to determine 1) whether intravascular ultrasound (IVUS) was more sensitive than angiography for the detection of post-transplant coronary artery disease (PTCAD) in pediatric patients; and 2) whether those transplanted as neonates reacted differently than older patients. BACKGROUND Experience with IVUS for the diagnosis of PTCAD in children is limited. METHODS Patients were divided into two groups: those transplanted as neonates (early group) and those transplanted in infancy or childhood (late group). Morphometric analysis was performed, including maximal intimal thickness (MIT) and intimal index (II). Stanford classification was used to grade lesion severity. Acute rejection and cytomegalovirus (CMV) status were correlated with MIT and II. RESULTS Thirty children were studied (early group, n = 13; late group, n = 17). All segments studied were angiographically normal. Mean MIT and mean II were significantly greater in the late group (0.26 ± 0.14 vs. 0.13 ± 0.04 mm, p < 0.001 and 0.11 ± 0.07 vs. 0.07 ± 0.03 mm, p = 0.04, respectively). There was a significant correlation between MIT and II in those who had acute rejection in the late group. Patients in the late group who were CMV-positive had a significantly higher MIT compared with those in the late group with negative serology (p = 0.04). CONCLUSIONS Intravascular ultrasound was more sensitive than angiography in detecting PTCAD after pediatric heart transplantation. There is a possible role for acute rejection and CMV in the development of PTCAD.