Cardiac function in fetuses of poorly-controlled pre-gestational diabetic pregnancies--a pilot study

Glucose control during pregnancy in patients with type 1 diabetes correlates with fetal hemodynamics: a prospective longitudinal study

BACKGROUND

Maternal diabetes adversely affects fetal cardiovascular system development. Previous studies have reported that the fetuses of mothers with diabetes exhibit both structural and functional changes; nevertheless, prior studies have not examined the association between glucose control and fetal cardiac morphology and performance. Thus, the objective was to determine the association between fetal cardiac morphology and function and maternal glucose control in type 1 diabetes and to compare the differences in measured cardiac parameters between the fetuses of mothers with diabetes and healthy controls.

METHODS

In this prospective, longitudinal case-control study - including 62 pregnant women with type 1 diabetes mellitus and 30 healthy pregnant women - fetal cardiac assessment using B-mode, M-mode, and spectral pulsed-wave Doppler was performed in the second and third trimesters. In women with T1DM, glycated hemoglobin and data obtained from glucose sensors - including the percentage of time in, below, and above the range (TIR, TBR, and TAR, respectively), and coefficient of variation (CV) - were analyzed across three time periods: the last menstrual period to 13 (V1), 14-22 (V2), and 23-32 weeks (V3) of gestation. Fetal cardiac indices were compared between groups, and the correlation between glucose control and fetal cardiac indices was assessed.

RESULTS

At 28-32 weeks, the fetuses of women with T1DM exhibited increased left ventricular end-diastolic length, relative interventricular septum thickness, right ventricular cardiac output, and pulmonary valve peak systolic velocity compared with healthy controls. At 18-22 weeks, pulmonary and aortic valve diameters, left and right ventricular stroke volumes, and left cardiac output inversely correlated with the CV and glycated hemoglobin levels at V1 and V2. Furthermore, at 28-32 weeks, pulmonary and aortic valve diameters, left ventricular stroke volume, cardiac output, and right/left atrioventricular valve ratio inversely correlated with the TBR at V1, V2, and V3. Moreover, diastolic functional parameters correlated with the TAR and glycated hemoglobin levels, particularly after the first trimester.

CONCLUSION

In women with T1DM, maternal hyperglycemia during pregnancy correlates with fetal diastolic function, whereas glucose variability and hypoglycemia inversely correlate with fetal left ventricular systolic function in the second and third trimesters.

Evaluation of cardiac contractility of fetuses from pregestational diabetes mellitus pregnancies by three-dimensional ultrasound

OBJECTIVE

This study aimed to evaluate cardiac contractility in fetuses from pregestational diabetes mellitus pregnancies by three-dimensional ultrasound using spatiotemporal image correlation in rendering mode.

METHODS

A retrospective cross-sectional study was performed on 40 fetuses from nondiabetic pregnancies and 28 pregestational diabetic pregnancies between 20 and 33 weeks and 6 days. Cardiac contractility was assessed by measuring the ventricular myocardial area in diastole subtracted from the ventricular myocardial area in systole.

RESULTS

Pregestational diabetic pregnancies had a lower maternal age than nondiabetic pregnancies (26.7 vs. 39.9 years, p=0.019). Cardiac contractility in fetuses from diabetic and nondiabetic pregnancies was similar (p=0.293). A moderately positive and significant correlation was observed between gestational age and cardiac contractility (r=0.46, p=0.0004). A 1-week increase in gestational age was responsible for a 0.1386 cm2 increase in cardiac contractility.

CONCLUSION

Cardiac contractility as evaluated by three-dimensional ultrasound using spatiotemporal image correlation in rendering mode showed no significant differences across fetuses with and without pregestational diabetes.

Evaluation of fetal myocardial performance index in gestational diabetes mellitus

This study aimed to compare fetal myocardial performance index (MPI) between fetuses of pregnant women with gestational diabetes mellitus (GDM) and healthy controls and to evaluate the relationship between MPI and maternal glucose levels. This was a prospective study of 90 pregnant women, including 50 pregnancies with GDM (27 pregnancies with insulin-regulated GDM and 23 pregnancies with diet-regulated GDM) and 40 healthy controls. Isovolumetric contraction time (ICT) + isovolumetric relaxation time (IRT)/ejection time (ET) were used to calculate the MPI (MPI = [ICT + IRT]/ET). Fetal MPI, PR interval, E/A ratio, maternal plasma glucose levels on the day of MPI measurement, and neonatal outcomes were compared. The fetal left-MPI was significantly higher in the GDM group than healthy controls (0.43 ± 0.04 vs. 0.40 ± 0.06, p = 0.007). The best cut-off level for MPI was >0.41 to predict adverse perinatal outcomes (sensitivity: 70%, specificity: 68%, area under the curve: 0.715, 95% confidence interval: 0.5143-0.8205, p < 0.001). The fetal MPI values showed no correlation with maternal plasma fasting, postprandial glucose, and hemoglobin A1c (HbA1c) levels. Reduced E/A ratio, higher neonatal intensive care unit admissions, and the need for cesarean delivery were detected in the GDM group. Fetal MPI is impaired in women with GDM, and the need for insulin therapy is associated with higher MPI values and adverse neonatal outcomes. Fetal MPI can help detect fetuses with potential adverse outcome risks, owing to impaired fetal cardiac function.

Modified myocardial performance index for evaluation of fetal heart function and perinatal outcomes in intrahepatic pregnancy cholestasis

This study aims to evaluate cardiac function in cases of intrahepatic cholestasis of pregnancy (ICP) and compare results with those from healthy controls using the fetal left ventricular modified myocardial performance index (LMPI) and E-wave/A-wave peak velocities (E/A ratio). Moreover, the association between LMPI values, total bile acid (TBA) levels, fetal Doppler measurements, and adverse neonatal outcomes was evaluated. A prospective cross-sectional study of 120 pregnant women was conducted, with 60 having ICP and the other 60 serving as controls. Doppler ultrasound and two-dimensional gray-scale fetal echocardiography were used to calculate the LMPI values and E/A ratios, respectively. The association between LMPI values and TBA levels, fetal Doppler measurements, and adverse neonatal outcomes was evaluated. Fetal LMPI values were significantly higher in the ICP group than in the control group (0.54 ± 0.54 vs. 0.44 ± 0.03; p < 0.001), but the E/A ratio was similar in both groups (0.69 ± 0.10 vs. 0.66 ± 0.14; p = 0.203). TBA levels were positively and significantly correlated with LMPI values (r = 0.546, p < 0.01); however, no significant correlation was found between umbilical arterial pulsatility index values and LMPI values (r = 0.071, p > 0.01). LMPI values were not associated with adverse neonatal outcomes in ICP cases. Fetal cardiac function (LMPI) is associated with increased bile acid levels in ICP. However, because it was not associated with adverse neonatal outcomes in ICP cases, the clinical significance of this finding is unclear. Further studies are required to evaluate the implications of increased LMPI.

Recent Experimental Studies of Maternal Obesity, Diabetes during Pregnancy and the Developmental Origins of Cardiovascular Disease

Globally, cardiovascular disease remains the leading cause of death. Most concerning is the rise in cardiovascular risk factors including obesity, diabetes and hypertension among youth, which increases the likelihood of the development of earlier and more severe cardiovascular disease. While lifestyle factors are involved in these trends, an increasing body of evidence implicates environmental exposures in early life on health outcomes in adulthood. Maternal obesity and diabetes during pregnancy, which have increased dramatically in recent years, also have profound effects on fetal growth and development. Mounting evidence is emerging that maternal obesity and diabetes during pregnancy have lifelong effects on cardiovascular risk factors and heart disease development. However, the mechanisms responsible for these observations are unknown. In this review, we summarize the findings of recent experimental studies, showing that maternal obesity and diabetes during pregnancy affect energy metabolism and heart disease development in the offspring, with a focus on the mechanisms involved. We also evaluate early proof-of-concept studies for interventions that could mitigate maternal obesity and gestational diabetes-induced cardiovascular disease risk in the offspring.

4D imaging of fetal right ventricle-feasibility study and a review of the literature

Functional analysis of the fetal cardiovascular system is crucial for the assessment of fetal condition. Evaluation of the right ventricle with standard 2D echocardiography is challenging due to its complex geometry and irregular muscle fibers arrangement. Software package TOMTEC 4D RV-Function is an analysis tool which allows assessment of right ventricular function based on volumetric measurements and myocardial deformation. The aim of this study was to determine the feasibility of this method in fetal echocardiography. The retrospective study was conducted in the high-flow Referral Center for Fetal Cardiology. We recorded 4D echocardiographic sequences of 46 fetuses with normal hearts. Following parameters were calculated: end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF), right ventricle longitudinal free-wall (RVLS free-wall) and septal strain (RVLS septum). Tei index was calculated as a standard measure or RV function for comparison. 4D assessment was feasible in 38 out of 46 fetuses (83%). RV volumetric parameters—EDV, ESV and SV—increased exponentially with gestational age. Functional parameters—RV Tei index, EF and strains—were independent of gestational age. Mean EF was 45.2% (± 6%), RV free-wall strain was − 21.2% and RV septal strain was − 21.5%. There was a statistically significant correlation between septal and free-wall strains (r = 0.51, p = 0.001) as well as between EF and RV free-wall strain (r = − 0.41, p = 0.011). 4D RV assessment is feasible in most fetuses. Its clinical application should be further investigated in larger prospective studies.

Longitudinal assessment of ventricular strain, tricuspid and mitral annular plane systolic excursion (TAPSE and MAPSE) in fetuses from pregnancies complicated by diabetes mellitus

OBJECTIVES

To evaluate fetal cardiac function using myocardial deformation analyses, tricuspid annular plane systolic excursion (TAPSE), mitral annular plane systolic excursion (MAPSE) and diastolic function parameters in pregnancies complicated by maternal diabetes mellitus.

METHODS

Myocardial deformation using velocity vector imaging (VVI), TAPSE, MAPSE and diastolic function was measured in 126 women with uncomplicated singleton pregnancies and 50 women with diabetes mellitus. Women underwent ultrasound scans every four weeks from recruitment (18-28 weeks gestational age) until delivery.

RESULTS

Left ventricle strain and strain rate, right ventricle strain and strain rate, TAPSE, MAPSE and diastolic parameters were not different between the diabetic cohort and controls throughout gestation. We did not find any significant correlation between the fetal cardiac function parameters with parity or smoking status. There was however a significant difference in strain and strain rate values in the left ventricle, but not the right ventricle in women with BMI >30 kg/m², and reduced TAPSE values in this same group. Fetuses in the diabetes group had thicker interventricular septum (IVS) throughout gestation.

CONCLUSION

Myocardial deformation of the fetal left ventricle, as measured by VVI, and TAPSE were reduced in fetuses of mothers in association with maternal obesity but not in women with diabetes mellitus. No significant differences in the fetal cardiac function parameters measured were different between the two groups, except for IVS thickness.

Persistent Aortic Stiffness and Left Ventricular Hypertrophy in Children of Diabetic Mothers

Background

Fetuses of diabetic mothers develop left ventricular (LV) hypertrophy and are at increased long-term risk of cardiovascular disease. In our previous longitudinal study from midgestation to late infancy we showed persistence of LV hypertrophy and increased aortic stiffness compared with infants of healthy mothers, the latter of which correlated with third trimester maternal hemoglobin A1c. In the present study, we reexamined the same cohort in early childhood to determine if these cardiovascular abnormalities persisted.

Methods

Height, weight, and right arm blood pressure were recorded. A full functional and structural echocardiogram was performed with offline analysis of LV posterior wall and interventricular septal diastolic thickness (IVSd), systolic and diastolic function, and aortic pulse wave velocity. Vascular reactivity was assessed using digital thermal monitoring. Participants also completed a physical activity questionnaire.

Results

Twenty-five children of diabetic mothers (CDMs) and 20 children from healthy pregnancies (mean age, 5.6 ± 1.7 and 5.3 ± 1.3 years, respectively; P = not significant) were assessed. Compared with controls, IVSd z score was increased in CDMs (1.2 ± 0.6 vs 0.5 ± 0.3, respectively; P = 0.006), with one-fifth having a z score of more than +2.0. Aortic pulse wave velocity was increased in CDMs (3.2 ± 0.6 m/s vs 2.2 ± 0.4 m/s; P = 0.001), and correlated with IVSd z score (R² = 0.81; P = 0.001) and third trimester maternal A1c (R² = 0.65; P < 0.0001). Body surface area, height, weight, blood pressure, vascular reactivity, and physical activity scores did not differ between groups. Our longitudinal analysis showed that individuals with greater IVSd, and aortic stiffness in utero, early and late infancy also tended to have greater measures in early childhood (P < 0.001 and P < 0.0001, respectively).

Conclusions

CDMs show persistently increased interventricular septal thickness and aortic stiffness in early childhood.

Could the E/A ratio be included in the cardiological evaluation of the offspring of diabetic mothers? A case-control study in South Sardinia

INTRODUCTION

Diabetes mellitus (DM) is a chronic disease widespread in the world. Sardinia represents, together with Finland, the region with the highest incidence of type 1 DM (DM1), as well as a high prevalence of gestational DM (GDM). Despite the improvement in obstetric surveillance, perinatal and long-term adverse outcomes are still frequent in the offspring of diabetic mothers. During gestations complicated by DM, fetal heart is one of the most affected organ potentially undergoing structural heart defects or several degrees of fetal myocardium hypertrophy and impaired cardiac function.

AIM

The aim of our study was to evaluate, through echocardiographic examination, cardiac features and performance in a South Sardinian population of newborns of diabetic mothers comparing them to a group of control subjects.

CONCLUSIONS

In our sample, the E/A ratio resulted a significant marker of early diastolic dysfunction in asymptomatic neonates born by diabetic mothers, even if such result should be confirmed on larger samples.

Fetal myocardial deformation in maternal diabetes mellitus and obesity

OBJECTIVE

Experimental evidence suggests that changes in the fetal myocardium result from intrauterine effects of maternal diabetes mellitus and obesity. The aim of this study was to assess fetal cardiac function using two-dimensional speckle-tracking echocardiography to determine the effects of maternal diabetes and obesity on the fetal myocardium.

METHODS

Comparative cross-sectional evaluation of myocardial function in fetuses of mothers with diabetes mellitus (FDM) or obesity (FO) and normal gestational age-matched control fetuses (FC) was performed using two-dimensional speckle-tracking echocardiography at two centers.

RESULTS

In total, 178 fetuses (82 FDM, 26 FO and 70 FC) met the enrolment criteria. Mean gestational age at assessment was similar among groups: 25.3 ± 5.1 weeks for FDM, 25.0 ± 4.6 weeks for FO and 25.1 ± 4.9 weeks for FC. Mean maternal body mass index was significantly higher in FDM and FO groups compared with the FC group. Statistically significant differences in fetal cardiac function were detected between FDM and FC for global longitudinal strain (mean ± SD, -21.4 ± 6.5% vs -27.0 ± 5.2%; P < 0.001), global circumferential strain (mean ± SD, -22.6 ± 6.5% vs -26.2 ± 6.8%; P = 0.002), average longitudinal systolic strain rate (median, -1.4 (interquartile range (IQR), -1.7 to -1.1)/s vs -1.6 (IQR, -2.0 to -1.4)/s; P = 0.001) and average circumferential systolic strain rate (median, -1.4 (IQR, -1.9 to -1.1)/s vs -1.6 (IQR, -2.1 to -1.3)/s; P = 0.006). Cases of non-obese FDM also had abnormal strain parameters compared with FC. Global longitudinal strain (mean ± SD, -21.1 ± 7.5%) and average circumferential systolic strain rate (median, -1.3 (IQR, -1.8 to -1.1)/s) were significantly lower in FO compared with FC.

CONCLUSIONS

Unfavorable changes occur in the fetal myocardium in response to both maternal diabetes mellitus and obesity. The long-term prognostic implications of these changes require further study. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Evaluation of the regional ventricular systolic function by two-dimensional strain echocardiography in gestational diabetes mellitus (GDM) fetuses with good glycemic control

OBJECTIVE

The aim is to quantitatively assess regional ventricular systolic function by two-dimensional strain (2DS) echocardiography in gestational diabetes mellitus (GDM) fetuses with good glycemic control.

METHODS

We studied 60 consecutive normal fetuses and 35 fetuses of GDM mothers with good glycemic control by echocardiography. M-mode and two-dimensional echocardiography were used to measure ejection fraction and wall dimensions of left ventricle and right ventricle. Both left and right ventricle peak systolic myocardial strain values were obtained by 2DS echocardiography.

RESULTS

Compared with normal fetuses, the thickness of the interventricular septum (IVS) and the thickness of right ventricular wall were significantly increased in GDM fetuses (p < 0.05). Compared with those of normal fetuses, the peak systolic myocardial strain decreased significantly in the apical segments of the IVS and the apical segments of the left ventricular lateral wall in GDM fetuses (p < 0.05), as well as the apical and middle segments of right ventricular wall in GDM fetuses (p < 0.05). Peak negative 2DS values in 60 normal fetuses increased with the gestational age, showing a significant linear correlation(r = -0.625, p < 0.001). The average ventricular strain was not correlated to ventricular wall thickness (r = 0.127, p = 0.394).

CONCLUSIONS

2DS is a feasible approach to assess regional ventricular systolic function in the fetal hearts and it can be used to examine cardiac systolic function in GDM fetuses with good glycemic control.

Evaluation of conventional Doppler fetal cardiac function parameters: E/A ratios, outflow tracts, and myocardial performance index

Structural evaluation of the fetal heart is well established. Functional evaluation using pulsed-wave Doppler may also be performed. E/A ratios express the relationship between the maximal velocities of the E and A waveforms of ventricular filling. In normal fetuses, E/A ratios are usually <1 but show a constant increment during gestation, mainly related to the increment of the E wave. In intrauterine growth restriction (IUGR) fetuses, E/A ratios are lower compared to values in normally grown fetuses at the same gestational age. Cardiac outflows provide information on the time-velocity integral that, combined with the vessel area, allows calculation of the left and right cardiac outputs. In normal fetuses there is a predominance of the right ventricle (55-60%) in contributing to the combined cardiac output. In IUGR fetuses this predominance shifts to the left ventricle in order to increase the flow to the upper part of the fetal body and brain. The myocardial performance index (MPI) also provides information on systolic and diastolic cardiac function. The MPI is an early and consistent marker of cardiac dysfunction which becomes altered in early stages of chronic hypoxia or in cases with cardiac overload such as in twin-to-twin transfusion syndrome.

Ductus venosus velocimetry in monitoring pregnancy in women with pregestational diabetes mellitus

OBJECTIVE

The purpose of this research was to assess the ability of ductus venosus (DV) Doppler velocimetry to predict adverse perinatal outcome in pregnancies complicated by pre-existing diabetes mellitus.

METHODS

This was a prospective study conducted at a tertiary referral obstetric facility in Brisbane, Australia. The study group included women with pregestational diabetes mellitus who delivered in the hospital between 1 January 1995 and 31 December 2006. The DV Doppler index was defined as abnormal if the DV peak velocity index for veins (PVIV) was equal to or greater than the 95(th) percentile for gestation. Adverse perinatal outcome included one or more of the following criteria: small-for-gestational-age infant; Cesarean section for non-reassuring fetal status; fetal acidemia at delivery; a 1-min Apgar score of <or= 3; a 5-min Apgar score of < 7; hypoxic ischemic encephalopathy; and stillbirth or neonatal death. The maternal characteristics and perinatal outcomes of pregnancies with normal or abnormal DV Doppler indices were compared.

RESULTS

Eighty-two pregestational diabetic pregnancies were studied and an abnormal DV-PVIV was identified in 25 (30.5%). Adverse perinatal outcome was identified in eight of 25 (32.0%) pregnancies with an abnormal DV-PVIV compared to seven of 57 (12.3%) pregnancies with a normal DV-PVIV (P < 0.05). The sensitivity of the DV-PVIV in predicting adverse perinatal outcomes in pregestational diabetic pregnancies was 53.3%, the specificity was 74.6%, the positive predictive value was 32.0% and the negative predictive value was 87.7%.

CONCLUSION

It may be useful to include DV-PVIV in the antenatal screening of pregnancies complicated by pregestational diabetes.

Modified myocardial performance index for evaluation of fetal cardiac function in pre-eclampsia

OBJECTIVE

To assess cardiac function by means of the modified myocardial performance index (Mod-MPI) in fetuses of pre-eclamptic mothers without intrauterine growth restriction and to compare this with values from normal controls.

METHODS

A cross-sectional study was conducted including a total of 72 fetuses at between 26 and 40 weeks' gestation. Forty fetuses of healthy mothers were assigned as the control group (Group I) while 15 fetuses of mildly pre-eclamptic mothers constituted Group II and 17 fetuses of severely pre-eclamptic mothers constituted Group III. Two-dimensional gray-scale and Doppler fetal echocardiography was used to exclude cardiac anomalies and calculate the Mod-MPI.

RESULTS

The mean+/-SD Mod-MPI values of Groups I, II and III were 0.43+/-0.045, 0.44+/-0.064 and 0.44+/-0.064, respectively (P=0.680). The mean aortic peak systolic velocity (PSV), the mean mitral valve early ventricular filling (E-wave) and active atrial filling (A-wave) peak velocities were significantly lower in fetuses of severely pre-eclamptic mothers than in fetuses of mildly pre-eclamptic mothers and control fetuses.

CONCLUSION

The fetal global myocardial function assessed by Mod-MPI does not seem to change in mild or severe pre-eclampsia. The lower mitral E-wave and A-wave peak velocities and the lower aortic PSV seem to reflect the increased cardiac afterload against which the fetal heart has to work, rather than systolic or diastolic cardiac dysfunction, in the fetuses of severely pre-eclamptic mothers.

Aortic and ventricular dilation and myocardial reduction in gestation day 17 ICR mouse fetuses of diabetic mothers

BACKGROUND

Maternal diabetes mellitus is associated with increased fetal teratogenesis, including cardiovascular defects. Information regarding cardiovascular changes in late-gestation fetal mice, related to maternal hyperglycemia, is not present in the literature.

METHODS

Late-gestation fetal heart and great vessel morphology were analyzed in fetuses from control and diabetic mice. Female ICR mice were injected with streptozocin (200 mg/kg IP) prior to mating to induce diabetes (n = 8). Nonhyperglycemic females were used as controls (n = 8). At day 17 of gestation, females were euthanized and one fetus was arbitrarily selected per litter to analyze the heart and great vessels. Six additional fetuses from different litters, showing external malformations (spina bifida and/or exencephaly), were also evaluated from the diabetic group. Fetal thoraxes were processed using routine histopathologic techniques, and 7-mum transversal sections were stained with hematoxylin-eosin. Digital images of sections were made and analyzed using NIH Image J software to compare regional cardiac development. Student's t tests for means were performed to determine differences between groups (p < .05).

RESULTS

Maternal hyperglycemia caused a dilation of late-gestation fetal ventricular chambers, a reduction of total ventricular myocardial area, and an increase in transversal ascending thoracic aortic area. Three of six fetuses that displayed external malformations showed an overt cardiac defect, beyond the ventricular and myocardial changes.

CONCLUSIONS

Maternal hyperglycemia altered morphology of the late-gestation fetal mouse heart. Postnatal persistence or consequences of late-gestation heart chamber dilation and myocardial reduction are not yet known.

Maternal diabetes and the fetal heart

Maternal diabetes mellitus significantly affects the fetal heart and fetal-placental circulation in both structure and function. The influence of pre-conceptional diabetes begins during embryonic development in the first trimester, with altered cardiac morphogenesis and placental development. It continues to have an influence on the fetal circulation through the second and third trimesters and into the perinatal and neonatal period.

Increased periconceptual maternal glycated haemoglobin in diabetic mothers reduces fetal long axis cardiac function

OBJECTIVE

To compare ventricular long axis function in fetuses of diabetic mothers (FDM) with contemporaneously studied normal controls (N) and to assess the effect of pre-pregnancy diabetic control on these measurements.

DESIGN

Long axis function was compared in 41 FDM and 159 N fetuses in a cross sectional observational study.

SETTING

Fetal medicine unit.

METHODS AND RESULTS

Echocardiography confirmed structural normality. Pulsed wave valvar Doppler velocimetry, lengthening and shortening myocardial velocities, and amplitude of ventricular long axis movement were recorded at the base of the left and right ventricular free walls and septum. Periconceptual diabetic control was assessed by haemoglobin A1c (HbA1c) in early pregnancy. Doppler and myocardial velocities were negatively related and myocardial thickness was positively related with HbA1c. In both cohorts all variables except mitral and tricuspid late filling (A wave) velocities were dependent on gestational age. FDM gestational age related values were higher for most variables and robust analysis of covariance showed significantly different maturation patterns in mitral valve E:A ratio (p = 0.036) and pulmonary velocity (p = 0.04), late lengthening myocardial velocities (left p = 0.016 and right p = 0.066), left myocardial shortening velocities (p = 0.008), and left free wall (p = 0.03) and septal (p = 0.04) amplitude of motion. FDM septal thickness was significantly increased throughout gestation (p < 0.0001).

CONCLUSION

Periconceptual diabetic control influences fetal cardiac performance and myocardial hypertrophy but, unlike the pathophysiology of adult ventricular hypertrophy, is accompanied by functional adaptation. It is unlikely to explain the increased rate of late stillbirth observed in diabetic pregnancies.

Antenatal fetal surveillance

PURPOSE OF REVIEW

Antenatal fetal surveillance is a field of increasing importance in modern obstetrics, especially as results in perinatal care have recently made dramatic progress. It is an evolving field, and it is no longer acceptable just to wait and see when problems arise in pregnancy. During the past few decades many studies have shown that antenatal surveillance in unselected populations is of little value. However, high-risk patients benefit from antenatal fetal surveillance, especially women with pregnancy problems associated with intrauterine growth restriction.

RECENT FINDINGS

This review shows that modern antenatal fetal surveillance is based on fetal heart rate monitoring, ultrasound biometry and amniotic fluid assessment, Doppler blood flow studies of fetal and uteroplacental circulation, and an evaluation of biophysical fetal parameters.

SUMMARY

Used in combination these methods lead to improvements in fetal morbidity and mortality. The aim of future research should be to minimize the risks of fetal morbidity and mortality further by the optimal timing of delivery. Better organization of healthcare systems may improve our ability to identify at-risk patients during pregnancy. There is potential to improve the specificity of fetal surveillance tests, e.g. better methods of biometry and amniotic volume estimation with three-dimensional ultrasound and measurements of subcutaneous tissue. Improved knowledge of fetal physiology can be gained from research on fetal circulation with Doppler studies. Computer analysis of the fetal heart rate can increase the specificity of that test, and artificial neural networks may enhance the ability to evaluate the optimal use of integrated testing.