Reference values for left and right ventricular systolic-to-diastolic duration ratio (SDR) found using both spectral and tissue Doppler of fetal heart between 20 and 36+6 weeks of gestation.

PURPOSE: To establish reference values for the systolic-to-diastolic duration ratio (SDR) of the left ventricle (LV) using spectral Doppler, as well as for the SDR' of the interventricular septum (SEP), LV, and right ventricles (RV) using tissue Doppler of the fetal heart. METHOD: This prospective and cross-sectional study evaluated 374 low-risk singleton pregnancies from 20 to 36 + 6 weeks of gestation. The ventricular filling time (FT) was obtained from LV inflow using spectral Doppler. Tissue Doppler was used to assess the FT of each ventricle by placing the cursor at the atrioventricular junction marked by the mitral and tricuspid valves, respectively. SDR was calculated as the sum of the isovolumic contraction time (ICT) and the ejection time (ET) divided by the sum of the isovolumic relaxation time (IRT) and the ventricular FT. We used regression analysis to obtain the best-fit model polynomial equation for the parameters. The concordance correlation coefficient (CCC) was used to assess intra- and inter-observer reproducibility. RESULTS: SDR and SDR' LV showed a progressive decrease with gestational age (GA); the SDR' RV and SDR' SEP did not show a significant decrease with advancing GA. The SDR LV (r = 0.29, p < 0.0001), SDR' RV (r = 0.21, p < 0.0001), SDR' LV (r = 0.20, p = 0.0001), and SDR' SEP (r = 0.25, p < 0.0001) showed a significant weak positive correlation with fetal heart rate. The inter-observer SDR' SEP measurements demonstrated poor reproducibility (CCC: 0.50), whereas intra-observer SRD LV measurements demonstrated moderate reproducibility (CCC: 0.78). CONCLUSIONS: Reference values for SDR SEP, LV, and RV using spectral and tissue Doppler of fetal heart were established between 20 and 36+6 weeks of gestation.

Fetal Cardiac Function and Ventricular Volumes Determined by Three-Dimensional Ultrasound Using STIC and VOCAL Methods in Fetuses from Pre-gestational Diabetic Women.

To assess the fetal cardiac function and ventricular volumes by three-dimensional (3D) ultrasound using spatio-temporal image correlation (STIC) and virtual organ computer-aided analysis (VOCAL) methods in fetuses from pre-gestational diabetic women. This was a prospective and cross-sectional study that evaluated 53 fetuses from pre-gestational diabetic women and 53 fetuses from healthy mothers between 20 and 34 weeks of gestation. Only fetuses with no structural or genetic abnormalities and singleton pregnant women were included in this study. The fetal cardiac volumes were assessed by STIC and VOCAL methods. The ejection fraction, stroke volume, and cardiac output were calculated from these measurements to evaluate fetal cardiac function. The Mann-Whitney U test was performed to compare the two groups. For calculation of intra- and interobserver reproducibility's, we used concordance correlation coefficients. The mean differences in the right atrial volumes between the diabetic and normal groups ranged from 0.05 mL to 0.1 mL (p = 0.917 and 0.355, respectively). The median of left atrium (LA) volume measurement in pre-gestational diabetic group was significantly lower than healthy mothers (LA: 0.62 vs. 0.68 mL; p < 0.001). The fetal right and left ventricular volumes were similar in both groups. No significant differences in ejection fraction, stroke volume and cardiac output were observed (p value range 0.086-0.815). The majority of fetal atrial/ventricular volumes showed good intra- and interobserver reliabilities. Conversely, the majority cardiac function parameters showed poor intra- and interobserver agreements. STIC and VOCAL methods gave reproducible quantitative results for fetal atrial and ventricular volumes. Significant differences in fetal left atrial volumes were observed between the two groups, which be related to LA atrial dysfunction and /or left ventricle (LV) compliance, reflecting earlier stages of cardiac dysfunction.