Serial Changes in Right Ventricular Systolic Function Among Rejection-Free Children and Young Adults After Heart Transplantation

Abstract

Evolution of right ventricular (RV) systolic function after pediatric heart transplantation (HT) has not been well described. We analyzed echocardiograms performed over the first year after HT among children and young adults who remained rejection-free. Ninety-six patients (median age 7.1 [0.1-24.4] years at HT) were included: 22 infants (≤1year) and 74 noninfants (>1year). Two-dimensional tricuspid annular plane systolic excursion (TAPSE), tissue Doppler-derived tricuspid annular systolic velocity (S'), fractional area change (FAC), myocardial performance index (MPI), and two-dimensional speckle-tracking-derived RV global longitudinal (GLS) and free wall strain (FWS) were assessed. All measures of RV function were impaired immediately after HT and significantly improved over the first year: TAPSE z-score (-8.15±1.88 to -3.94±1.65, P<.0001), S' z-score (-4.30±1.36 to -2.28±1.33, P<.0001), FAC (24.37%±7.71% to 42.02%±7.09%, P<.0001), MPI (0.96±0.47 to 0.41±0.22, P<.0001), GLS (-10.37%±3.86% to -21.05%±3.41%, P<.0001), and FWS (-11.2%±4.08% to -23.66%±4.13%, P<.0001). By 1year post-HT, TAPSE, S', GLS, and FWS, remained abnormal, whereas FAC and MPI nearly normalized. Patients transplanted during infancy demonstrated better recovery of RV systolic function. Although RV systolic function improved over the first year after HT in children and young adults without rejection, measures that assess longitudinal contractility remained abnormal at 1year post-HT. These findings contribute to our understanding of RV myocardial contractility after HT in children and young adultsand improve our ability to assess function quantitatively in this population.