The use of Doppler tissue imaging to predict cellular and antibody-mediated rejection in pediatric heart transplant recipients

DTI indices have been associated with cellular rejection in adult heart transplant recipients, but their predictive value in pediatric recipients is unknown. The purpose of this study was to evaluate DTI measures in the detection of cellular and AMR in pediatric heart transplant recipients. One hundred and forty-eight pediatric heart transplant recipients who had 267 cardiac catheterization procedures with EMB, echocardiogram with DTI, and BNP level performed on the same day were included in the study. For the mitral and tricuspid valves, the ratios (E/E') between the early diastolic inflow velocity by pulsed Doppler (E, m/s) and the early diastolic annular velocity by DTI (E', m/s) were obtained and compared between subjects with and without rejection. Of the 148 recipients, 30 subjects had a total of 37 episodes of rejection: 10 cellular (>= 1B), 17 AMR, and 10 biopsy-negative clinical rejection. Mitral and tricuspid valve E/E' ratios were significantly higher in rejectors than in non-rejectors (5.5 +/- 1.3 vs. 4.4 +/- 1.4, p < 0.001 and 4.9 +/- 2.1 vs. 4.1 +/- 1.5, p < 0.01, respectively). By multivariate linear regression, mitral valve E/E' was an independent predictor of rejection. Mitral and tricuspid valve E/E' < 5.0 had 93% and 89% NPV, respectively, for rejection. Mitral and tricuspid valve E/E' ratios < 5.0 may be useful non-invasive screening measures to exclude rejection in pediatric heart transplant recipients.