Color tissue doppler imaging of tricuspid annular plane systolic and diastolic excursion in children: A comparison of normal, volume-overloaded and pressure overloaded right ventricles

BACKGROUND

Tricuspid annular plane (TAP) systolic excursion (TAPSE) is a reproducible M-mode parameter for the measurement of longitudinal shortening of the right ventricle (RV). To date, all attention has been focused on the systolic excursion of TAP and the diastolic excursion of the annular plane back to the base has been ignored. This study aims to compare the quantitative (excursion, slope, and duration) and qualitative (velocity, acceleration, and indentation) characteristics of TAP systolic and diastolic excursion, using color tissue Doppler imaging, in three groups of children with normal RV (NORV), volume overloaded RV (VORV), and pressure overloaded RV (PORV) and normal pulmonary arterial pressure.

SUBJECTS AND METHODS

A prospective case-control study was performed in three groups of children with normal heart, VORV and PORV. TAPSE and tricuspid annular plane diastolic excursion (TAPDE) were quantitatively and qualitatively analyzed and compared between the three groups. Statistical analysis was performed using IBM SPSS Statistics for Windows.

RESULTS

TAPSE, TAPDE, TAPSE slope, TAPSE slope/TAPDE slope, TAPDE duration and TAPDE duration/RR interval were lower in PORV (TAPSE: PORV: 14.45 ± 4.30, NORV: 20.45 ± 5.46, P = .003, TAPDE:PORV: 14.39 ± 4.61, NORV: 20.28 ± 5.65, P = .004, TAPSE slope:PORV: 4.79 ± 1.40, NORV: 7.15 ± 1.98, P = .001, .001, TAPDE duration:PORV: 201.1 ± 87.9 ms, NORV: 292.1 ± 97.9, P = .006, TAPDE duration/RR interval: PORV: .37 ± .09, NORV: .48 ± .08, P = .0002).

CONCLUSION

Pressure-overload on RV produced more impairment of TAPSE and TAPDE patterns than volume overload. Values of TAPSE and TAPDE in patients with VORV and PORV stay in two ends of the normal spectrum. The harmful impact of pre-tricuspid volume overload seems to be less than the post-tricuspid volume overload.

Assessment of human fetal cardiac autonomic nervous system development using color tissue Doppler imaging

Objectives

Functional development of the fetal cardiac autonomic nervous system (cANS) plays a key role in fetal maturation and can be assessed through fetal heart rate variability (fHRV)‐analysis, with each HRV parameter representing different aspects of cANS activity. Current available techniques, however, are unable to assess the fHRV parameters accurately throughout the whole pregnancy. This study aims to test the feasibility of color tissue Doppler imaging (cTDI) as a new ultrasound technique for HRV analysis. Secondly, we explored time trends of fHRV parameters using this technique.

Methods

18 healthy singleton fetuses were examined sequentially every 8 weeks from 10 weeks GA onwards. From each examination, 3 cTDI recordings of the four‐chamber view of 10 seconds were retrieved to determine accurate beat‐to‐beat intervals. The fHRV parameters SDNN, RMSSD, SDNN/RMSSD, and pNN10, each representing different functional aspects of the cANS, were measured, and time trends during pregnancy were explored using spline functions within a linear mixed‐effects model.

Results

In total, 77% (95% Cl 66–87%) of examinations were feasible for fHRV analysis from the first trimester onwards, which is a great improvement compared to other techniques. The technique is able to determine different maturation rates of the fHRV parameters, showing that cANS function, presumably parasympathetic activity, establishes around 20 weeks GA and matures rapidly until 30 weeks GA.

Conclusions

This is the first study able to assess cANS function through fHRV analysis from the first trimester onwards. The use of cTDI to determine beat‐to‐beat intervals seems feasible in just 3 clips of 10 seconds, which holds promise for future clinical use in assessing fetal well‐being.

Evaluation of right ventricular function in fetal hypoplastic left heart syndrome by color tissue Doppler imaging

OBJECTIVE

Postnatal outcome of fetuses with hypoplastic left heart syndrome (HLHS) is determined mainly by right ventricular function. Our study examines whether there are differences in right ventricular function during gestation of fetuses with HLHS compared with healthy fetuses.

METHODS

A prospective study was conducted including 20 fetuses with HLHS and 20 gestational age-matched controls. Peak systolic and diastolic right ventricular free wall velocities were assessed using color tissue Doppler imaging (c-TDI). Subsequently, isovolumic time intervals, ejection time (ET'), E'/A' ratio and tissue Doppler-derived myocardial performance index (MPI') were calculated. Possible changes to c-TDI indices during the course of pregnancy in both the HLHS group and the control group were investigated.

RESULTS

Examination of right ventricular function revealed significantly lower E' velocities (13.6 vs 21.0 cm/s; P = 0.017) and E'/A' ratios (0.55 vs 0.76; P = 0.012) and prolonged isovolumic contraction time (ICT') (57.0 vs 45.7 ms; P = 0.008) in the HLHS group compared with healthy fetuses. Furthermore, isovolumic relaxation time and MPI' increased significantly with gestational age in HLHS fetuses but not in controls. Values for systolic and diastolic peak velocities (E', A', S'), ET' and ICT' did not change significantly during gestation in either group.

CONCLUSION

Right ventricular function in HLHS is altered as early as in fetal life, well before palliative surgery is performed. Future research should provide further insight into ventricular remodeling during gestation in cases of HLHS. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.