Annular and septal Doppler tissue imaging in children: normal z-score tables and effects of age, heart rate, and body surface area.

The aim of this study was to construct normal z-score tables for longitudinal directed Doppler tissue imaging (DTI) systolic wave (S), DTI early diastolic wave (E'), and DTI late diastolic wave (A') at the mitral valve annulus (MV), superior ventricular septum (VS), and tricuspid valve annulus (TV) in pediatric patients. We analyzed normal echocardiograms from 634 children aged 1 day to 18 years, heart rate (HR) range of 50 to 194/min, and body surface area (BSA) range of 0.1 to 2.8 m2. First we determined the effects of age, HR, and BSA on the S, E', and A' at the MV, VS, and TV sampling sites by univariate analysis. Next we determined which of the 3 factors, age versus HR versus BSA, correlated best with the S, E', and A' at each of the 3 sampling sites by multivariate analysis. Finally, using the specific factor of age versus HR versus BSA that best predicted a particular DTI wave at a particular sampling site, we constructed z-score tables for each of the 3 DTI parameters at each of the 3 sampling sites. The S range was: MV = 2.2 to 23.2 cm/s; VS = 1.6 to 22.3 cm/s; and TV = 1.8 to 31.3 cm/s. By univariate analysis the S correlated negatively with HR and positively with age and BSA with strong correlations at all 3 sites. By multiple regression analysis the S correlated best with age at all 3 sites. The E' range was: MV = 2.4 to 37.1 cm/s; VS = 1.8 to 29.0 cm/s; and TV = 2.4 to 32.4 cm/s. The E' varied negatively with HR and positively with age and BSA with strong correlations by univariate analysis at all 3 sites. By multiple regression, the E' correlated best with age for the VS and TV sites, and correlated best with HR at the MV site. The E' at the MV site also strongly correlated with age by multivariate analysis. The A' range was: MV = 2.9 to 20.7 cm/s; VS = 2.7 to 18.2 cm/s; and TV = 1.1 to 29.3 cm/s. The A' had a strong positive correlation with HR at all 3 sites, a strong negative correlation with BSA and age at the TV site only, with no statistical significant correlation of the MV and VS site A' to BSA or age. Using multiple regression analysis the A' correlated best with HR at all 3 sites. Z-score tables developed from a large sample volume encompassing the entire spectrum of ages, HR, and BSA encountered in pediatric patients and developed using the strongest predicting factor serve as reference data for longitudinal directed DTI annular and septal S, E', and A' normal values in children.