Objective Assessment of cardiac function by speckle tracking (2D-S) echocardiography in the transitional period from foetal to neonatal life in a healthy population.
Methods Ultrasound assessment of cardiac function of 30 healthy foetuses at the gestational age of 28 and follow-up after birth using 2-D strain derived novel parameters such as strain (S), strain rate (SR), tissue velocities, MPI- and E/E’-index, E/A- and E’/A’-rate of both right (RV) and left ventricles (LV) and interventricular septum (IVS) and comparison to conventionally measured cardiac stroke volume (SV), cardiac output (CO) and ejection fraction (EF).
Results Ultrasound performance and analysis is technically feasible in all 30 foetuses and in the neonatal period. In foetuses, tissue velocities and SR measurements are homogenous for all regions of interest in both ventricles, and strain increases from apex to basis and is higher in the RV compared to LV. All calculated indices are almost identical for RV and LV.
After birth, strain and strain rate exhibit significantly lower values (p<0.001) and systolic tissue velocities are significantly (p=0.001) higher in comparison to fetal values in both chambers and in all regions of interest. The conventional methods for measuring EF, SV and CO show higher variability and lower reproducibility.
Conclusion The haemodynamic changes in cardiac function from foetal to neonatal life can be assessed by the novel method of speckle-tracking echocardiography which seems to be more reliable than conventional ultrasound techniques. Therefore, we recommend using speckle-tracking technique in routine follow-up of myocardial function in foetuses and neonates.