Preload dependence of Doppler tissue imaging-derived indices in adolescents

Doppler tissue imaging (DTI) has been proposed as a tool for evaluation of diastolic function. Controversy exists regarding whether DTI measurements are influenced by preload. To determine the influence of preload reduction on DTI, we studied 17 patients (mean age 17 +/- 1.82 years) with end-stage renal disease and without overt heart disease, using DTI before and after hemodialysis (HD). Peak systolic (S), peak early diastolic (Ea), and peak late diastolic (Aa) velocities, and tissue Doppler-derived Tei index (the sum of the isovolumetric contraction and relaxation times divided by the ejection time: TDE-Tei), were determined for each patient from the septum, and lateral mitral and lateral tricuspid annuluses. The Ea of the mitral annulus (12.47 +/- 4.51 cm/s to 10.71 +/- 5.18 cm/s, P = 0.023), isovolumetric contraction time (ICT) of the mitral annulus (85.29 +/- 33.66 ms to 68.76 +/- 17.24 ms, P = 0.031) and Aa of the lateral tricuspid annulus (15.94 +/- 6.46 cm/s to 12.47 +/- 3.85 cm/s, P = 0.044) decreased significantly after HD. With weight loss of more than 1.5 kg, significant changes in the TDE-Tei index of the septum was observed (P = 0.036). From these findings, it is concluded that the Ea of the mitral annulus and the Aa of the tricuspid annulus are decreased by acute preload reduction. The TDE-Tei index is affected by preload reduction of more than 1.5 kg; therefore, it seems necessary to consider the preload status of HD patients when myocardial function is assessed by DTI.