Cardiac allograft function during the first year after transplantation in rejection-free children and young adults.

BACKGROUND: Allograft dysfunction is a common finding early after heart transplant (HT). We sought to assess the recovery of left (LV) and right ventricular (RV) function during the first year after HT in children and young adults using pulsed-wave tissue Doppler imaging.

METHODS AND RESULTS: We analyzed serially performed echocardiography in 44 pediatric HT recipients (median age: 7.3 years at HT) who remained rejection-free during the first year post-transplant. Age-based normative values for systolic (S'), early-diastolic (E'), and late-diastolic (A') velocities obtained using pulsed-wave tissue Doppler imaging in 380 healthy children were used to transform patient data into z scores. Pulsed-wave tissue Doppler imaging studies ≤10 days post-HT demonstrated biventricular systolic and diastolic dysfunction with most prominent impairment in RV systolic function (S' z score -2.7±0.8), RV early-diastolic filling (E' z score -2.3±1.1), and LV early-diastolic filling (E' z score -2.3±1.1). LV systolic function (S' z score) and late-diastolic filling (A' z score) improved to normal in 11 to 30 days, LV early-diastolic filling (E' z score) in 4 to 6 months, and RV early-diastolic filling in 6 to 9 months (P<0.001 for all on longitudinal analysis). However, RV systolic function (RV S' z score -1.2±1.1) remained impaired 1-year post-transplant. Analysis of serial cardiac catheterization studies showed that RV and LV filling pressures were elevated early post-HT and declined gradually during the first year post-transplant.

CONCLUSIONS: Pediatric HT recipients have biventricular dysfunction using pulsed-wave tissue Doppler imaging early after HT with most significant impairment in RV systolic function and RV and LV early-diastolic filling. Although other aspects of LV and RV function normalize in 6 to 9 months, RV systolic function remains abnormal 1 year-post-transplant.