Cardiac dysfunction by tissue doppler in earty-and late-onset fetal growth restriction

SUMMARY 1) Background Fetal growth restriction (FGR) is present in 5-10% of the pregnancies and is associated to high perinatal and long-term cardiovascular morbidity. Subclinical cardiac dysfunction has previously been described in severe and early FGR cases, but not in milder forms of late-FGR. The main aim of this thesis was to assess cardiac function by new echocardiographic techniques on myocardial imaging as Tissue Doppler Imaging (TDI), in early- and late-onset FGR cases. 2) Methods First, tissue Doppler was applied in a cohort of normally growth fetuses by TDI in order to describe its reproducibility and construct reference ranges for fetal annular peak velocities and myocardial performance index at 24-41 weeks of gestation. Secondly, cardiac function including conventional echocardiographic parameters and TDI was evaluated in a cohort of early-onset growth restricted fetuses with abnormal umbilical artery (UA) Doppler and, finally, in a cohort of late-onset small for gestational age (SGA) fetuses with normal UA Doppler. 3) Results Fetal TDI measurements demonstrated a good reproducibility. GA and estimated fetal weight (EFW) adjusted reference ranges for tissue Doppler indices at 24-41 weeks of gestation were provided. TDI demonstrated the presence of both systolic and diastolic cardiac dysfunction in early-onset FGR fetuses. Late-onset FGR fetuses with normal UA were also associated with cardiac dysfunction detected by TDI. 4) Conclusions Early- and late-onset growth restricted fetuses are associated with cardiac dysfunction. Subclinical cardiac dysfunction could be present from early stages of fetal deterioration and could be detected using TDI