Evolution of the Fetal Atrioventricular Interval from 6 to 40 Weeks of Gestation

Fetal PR Interval in Pregnancies with Intrahepatic Cholestasis of Pregnancy: A Case-Control Study

OBJECTIVE

 This study had three purposes: first, to explore differences in fetal cardiac function in patients with and without intrahepatic cholestasis of pregnancy (ICP) based on PR interval (the interval between the beginning of the atrial contraction and the beginning of the ventricular contraction). Second, to explore a potential correlation between PR interval and bile acid levels in pregnant women with ICP. Third, to study changes in PR interval of fetuses from pregnant women with ICP after administration of ursodeoxycholic acid (UDCA).

STUDY DESIGN

 This was a prospective observational case-control study. ICP was defined as palmar plantar pruritus of nocturnal predominance for more than 1 week associated with a total bile acid level >10 μmol/L. Control cases were women with pregnancies scheduled for induction or elective cesarean section at term.

RESULTS

 One hundred and ten women with ICP and 72 controls were included in the study. Median gestational age at inclusion was 35.9 weeks. Median PR interval was significantly longer in fetuses of women with ICP (122 vs. 102 ms, p < 0.001). There was a significant correlation between bile acid levels and PR interval (rho = 0.723, p < 0.001). In 22 fetuses, the median PR interval decreased significantly following UDCA administration (134 vs. 118 ms, p = 0.004).

CONCLUSION

 PR interval is longer in fetuses of women with ICP. PR interval was significantly correlated with bile acid levels, and administration of UDCA significantly reduced PR interval.

KEY POINTS

· Differences in fetal cardiac function in patients with and without intrahepatic cholestasis.. · PR interval and bile acid levels in pregnant women with intrahepatic cholestasis.. · Changes in PR interval of fetuses from pregnant women with ICP after use of UDCA..

Assessment of fetal cardiac function in early fetal life: feasibility, reproducibility, and early fetal nomograms

BACKGROUND

Fetal cardiology has shown a rapid development in the past decades. Fetal echocardiography is not only used for the detection of structural anomalies but also to assess fetal cardiac function. Assessment of the fetal cardiac function is performed mostly in the second and third trimesters. The study of fetal cardiac function at the end of first trimester has not been investigated properly, and there is a lack of reference values at early gestational weeks.

OBJECTIVE

This study aimed to assess if the measurement of time-related parameters of cardiac function in the left ventricle of the fetal heart is feasible and reproducible at the end of the first trimester. If possible, we provide nomograms of these parameters from 11 to 13+6 gestational weeks.

STUDY DESIGN

We conducted a prospective observational study from March to September 2022. The study was carried out in 2 hospitals (Hospital Universitari Dexeus, Barcelona, and Hospital VITAHS 9 Octubre, Valencia, Spain). The scans were performed by 3 specialists in fetal medicine. The exclusion criteria were fetal cardiac rhythm abnormalities, abnormal nuchal translucency, abnormal ductus venosus, fetal malformations, stillbirth, estimated fetal weight <10 percentile, diabetes, and gestational hypertensive disorders. The cardiac function parameters studied in the left ventricle were isovolumetric contraction time, isovolumetric relaxation time, ejection time, filling time, cycle time, myocardial performance index, ejection time fraction, and filling time fraction. We study the feasibility and intra- and interobserver reproducibility of these parameters using the interclass correlation coefficient. Nomograms were created and the percentiles of the values of the different parameters were calculated.

RESULTS

A total of 409 cases were recruited but only 296 could be included in the statistical analysis once the exclusion criteria were applied. The intraobserver reproducibility study was excellent (interclass correlation coefficient >0.900), and the interobserver reproducibility study was good (interclass correlation coefficient >0.700). The data regression analysis showed that cycle time, filling time, isovolumetric contraction time, and filling time fraction increased with gestational age, whereas ejection time fraction decreased with gestational age and myocardial performance index (mean, 0.43±0.08), isovolumetric relaxation time (mean, 0.04±0.01), and ejection time (mean, 0.16±0.01) remained constant from 11 to 13 weeks.

CONCLUSION

The study of fetal cardiac function is feasible and reproducible at 11 to 13+6 gestational weeks. Nomograms of the studied parameters are provided.

Measurement of fetal atrioventricular intervals in pregnant women with anti-SSA/Ro antibodies

PURPOSE

The objective of our study was to compare and consider reference values of fetal atrioventricular (AV) intervals as measured by four different pulsed Doppler wave techniques (left ventricular inflow/outflow [LV in/out], pulmonary vein/pulmonary artery [PV/PA], innominate vein/ascending aorta [InnV/AA], and supra vena cava/ascending aorta [SVC/AA]) in pregnant women with anti-SSA/Ro antibodies.

METHODS

Between March 2014 and September 2020, 52 pregnant women with anti-SSA antibodies were enrolled. No bradyarrhythmia was observed in the group. A pulsed Doppler examination of the fetal heart was performed to obtain measurements of the mechanical Doppler AV interval. Doppler measurements were performed using four methods: LV in/out, PV/PA, InnV/AA, and SVC/AA. A statistical analysis was performed to examine the mean, standard deviation, significant difference, and correlation of the four methods. The detection rate of each method was also calculated.

RESULTS

There was no significant difference in the AV intervals between any of the four methods. There was also a positive correlation in the AV intervals of each of the four methods. The fetal heart rate and AV interval showed no correlation. The gestational age and AV interval also showed no correlation. The detection rate was highest for LV in/out (62.6%, 95% confidence interval: 56.5-68.4).

CONCLUSION

All four pulsed Doppler methods are useful for measuring AV intervals. The most practical method is LV in/out.