Diastolic performance assessed by tissue Doppler after pediatric heart transplantation

Diastolic performance, indexed by tissue Doppler imaging (TDI), has been reported to predict cellular rejection in adult heart recipients, but the predictive value of TDI after pediatric heart transplantation is unknown.

TDI-derived diastolic performance was studied in 37 pediatric (median age 2.54 years) heart recipients in the absence and presence of rejection. Maximum velocities in diastole of the left ventricular posterior wall thinning (diastvelLVPWmax) and medial mitral valve annulus (MVA) were determined in 160 echocardiograms from recipients who experienced either no rejection (Group 1, n = 22) or >or=1 rejection episode(s) (Group 2, n = 14) during the study interval (2 years). There was 1 death in the immediate post-transplant period not included in the analyses.

The diastvelLVPWmax determined by TDI in Group 1 increased during the first 90 days post-transplant (r = 0.31; p = 0.05), was heart-rate-dependent (r = 0.591; p < 0.001), and was significantly lower than the veILVPWmax determined from digitized M-mode tracings (116 +/- 31 vs 135 +/- 44 mm/s; p < 0.05). In a sub-group of children transplanted during the study and followed for >or=1 year (n = 9), diastvelLPWmax, determined by TDI, was lower in infant recipients (n = 6; 106.5 +/- 22 mm/s) than in older recipients (n = 3; 135 +/- 36 mm/s; p = 0.015). With rejection, diastvelLVPWmax, determined by M mode (147 +/- 13 vs 104 +/- 11 mm/s; p < 0.05), was decreased compared with baseline recipient studies prior to rejection. In contrast, rejection did not significantly change diastvelLVPWmax, as determined by TDI. MVA E/A (peak early-to-late diastolic velocity ratio) was significantly decreased with rejection (1.37 +/- 0.23 vs 0.92 +/- 0.22; p < 0.05). As a single parameter, an MVA E/A <1.1 was predictive of rejection in 4 of 10 recipients with MVA E/A >or=1.1 pre-rejection.

TDI-derived diastvelLVPWmax varied with age at transplant, heart rate and time post-transplant. A decrease in TDI-derived MVA E/A, but not diastvelLVPWmax, can be of additional predictive value in non-invasive surveillance for rejection in pediatric heart recipients.