Maternal echocardiographic changes in twin pregnancies with and without pre-eclampsia.

OBJECTIVE: Twin pregnancies are at increased risk of developing hypertensive disorders of pregnancy (HDP) compared with singleton pregnancies, resulting in a substantially higher rate of maternal and perinatal complications. The strain caused by twin pregnancy on the maternal cardiovascular system has not been studied extensively. The objective of this study was to evaluate the changes in maternal cardiac morphology and diastolic function in a cohort of women with normotensive and those with hypertensive twin pregnancies. METHODS: This was a cross-sectional study conducted at a tertiary referral university center. Women with singleton or twin pregnancy were enrolled prospectively to undergo maternal transthoracic echocardiography throughout pregnancy. Multiples of the median (MoM) were calculated for each index using a reference group of uncomplicated singleton pregnancies (n = 411) in order to adjust for changes associated with gestational age. Cardiac findings were indexed for body surface area and compared among normotensive twin pregnancies, singleton pregnancies complicated by HDP and twin pregnancies complicated by HDP. RESULTS: The total cohort included 119 HDP singleton pregnancies, 52 normotensive twin pregnancies and 24 HDP twin pregnancies. Left ventricular mass index (LVMi) MoM (median (interquartile range)) did not differ between singleton pregnancies complicated by HDP and normotensive twin pregnancies, but was significantly higher in HDP twin compared with HDP singleton pregnancies (1.31 (1.08-1.53) vs 1.17 (0.98-1.35), P = 0.032). Two diastolic indices, left atrial volume index MoM (1.12 (0.66-1.38) vs 0.65 (0.55-0.84), P = 0.003) and E/e' MoM (1.29 (1.09-1.54) vs 0.99 (0.99-1.02), P = 0.036), were significantly higher in HDP twin compared with normotensive twin pregnancies. In normotensive twin compared with HDP singleton pregnancies, stroke volume index (SVi) MoM was higher (1.20 (1.03-1.36) vs 1.00 (0.81-1.15), P = 0.004) and total vascular resistance index (TVRi) was lower (0.73 (0.70-0.86) vs 1.29 (1.04-1.56), P < 0.0001). In contrast, SVi MoM was lower (1.10 (1.02-1.35) vs 1.20 (1.03-1.36), P = 0.018) and TVRi was higher (1.00 (0.88-1.31) vs 0.73 (0.70-0.86), P = 0.029) in HDP twin compared with normotensive twin pregnancies. CONCLUSION: The maternal cardiovascular system is altered severely in twin pregnancy with or without HDP. Despite the low total vascular resistance, cardiac changes in normotensive twin pregnancies are comparable to those seen in singleton pregnancies complicated by HDP, reflecting the high cardiovascular demand imposed by twin pregnancy. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Outcome of twin-to-twin transfusion syndrome in monochorionic monoamniotic twin pregnancy: systematic review and meta-analysis.

OBJECTIVES: To explore the outcome of monochorionic monoamniotic (MCMA) twin pregnancies affected by twin-to-twin transfusion syndrome (TTTS). METHODS: MEDLINE and EMBASE databases were searched for studies reporting the outcome of MCMA twin pregnancies complicated by TTTS. The primary outcome was intrauterine death (IUD); secondary outcomes were miscarriage, single IUD, double IUD, neonatal death (NND), perinatal death (PND), survival of at least one twin, survival of both twins and preterm birth (PTB) before 32 weeks' gestation. Outcomes were assessed in MCMA twins affected by TTTS not undergoing intervention and in those treated with amniodrainage, laser therapy or cord occlusion. Subgroup analysis was performed including cases diagnosed before 24 weeks. Random-effects meta-analysis of proportions was used to analyze the data. RESULTS: Fifteen cohort studies, including 888 MCMA twin pregnancies, of which 44 were affected by TTTS, were included in the review. There was no randomized trial comparing the different management options in MCMA twin pregnancies complicated by TTTS. In cases not undergoing intervention, miscarriage occurred in 11.0% of fetuses, while the incidence of IUD, NND and PND was 25.2%, 12.2% and 31.2%, respectively. PTB complicated 50.5% of these pregnancies. In cases treated by laser surgery, the incidence of miscarriage, IUD, NND and PND was 19.6%, 27.4%, 7.4% and 35.9%, respectively, and the incidence of PTB before 32 weeks' gestation was 64.9%. In cases treated with amniodrainage, the incidence of IUD, NND and PND was 31.3%, 13.5% and 45.7% respectively, and PTB complicated 76.2% of these pregnancies. Analysis of cases undergoing cord occlusion was affected by the very small number of included cases. Miscarriage occurred in 19.2%, while there was no case of IUD or NND of the surviving twin. PTB before 32 weeks occurred in 50.0% of these cases. CONCLUSIONS: MCMA twin pregnancies complicated by TTTS are at high risk of perinatal mortality and PTB. Further studies are needed in order to elucidate the optimal type of prenatal treatment in these pregnancies. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Uterine artery Doppler, birth weight and timing of onset of pre-eclampsia: providing insights into the dual etiology of late-onset pre-eclampsia.

OBJECTIVE: To investigate the relationship between uterine artery Doppler ultrasound indices and birth weight in women with early-, intermediate- and late-onset pre-eclampsia as compared with women with uneventful pregnancy outcome. METHODS: In a retrospective, observational cohort study, uterine artery Doppler assessment was carried out at 18+0 to 23+6 weeks' gestation in 26,893 women attending for routine antenatal care in a tertiary care center. The mean resistance index (RI) and its relationship to the outcome of pregnancy and birth-weight centiles were evaluated. RESULTS: Uterine artery RI showed a significant, negative correlation with birth weight (r= -0.20, P<0.0001). Patients with early-onset pre-eclampsia had an increased prevalence of high uterine artery mean RI, above the 90(th) centile, corresponding to an increased proportion of small-for-gestational age (SGA) neonates with a birth weight below the 10(th) centile. In late-onset pre-eclampsia, however, there was an unexpectedly higher proportion of large-for-gestational-age (LGA) neonates with a birth weight above the 90(th) centile without a concurrent increase in the prevalence of low uterine artery mean RI below the 10(th) centile. CONCLUSIONS: The finding of a bimodal skewed distribution of birth weight, with neonates exhibiting a higher prevalence of both LGA and SGA with late-onset pre-eclampsia, indicates that there are two types of late-onset pre-eclampsia. These findings explain the poor performance of mid-trimester uterine artery Doppler in predicting pre-eclampsia at term and provide insights into the placental origins of the early and late forms of pre-eclampsia.

Mid-gestational maternal cardiovascular profile in preterm and term pre-eclampsia: a prospective study.

OBJECTIVE: Pre-eclampsia (PE) is associated with maternal cardiac remodelling and biventricular diastolic dysfunction. Preterm PE alone can also be associated with severe left ventricular hypertrophy and biventricular systolic dysfunction. The aim of this study was to assess whether the maternal cardiovascular profile at mid-gestation in nulliparous normotensive women differs in women destined to develop preterm PE versus those who will develop PE at term. DESIGN: Prospective study. SETTING: Tertiary referral university centre. POPULATION: A total of 269 women, including 152 at increased risk of developing PE as determined by mid-gestational uterine artery Doppler assessment. METHODS: Women underwent blood pressure profiling, echocardiography, cardiac tissue Doppler and strain rate analysis at 20-23 weeks of gestation. MAIN OUTCOME MEASURES: Mid-gestational cardiovascular profile in women with normal pregnancy and those that subsequently developed preterm or term PE. RESULTS: Pre-eclampsia subsequently developed in 46 women, including 18 with preterm PE. Women who subsequently developed PE, irrespective of gestation, had evidence of left ventricular concentric remodelling (33%) which was not found in the control women (P < 0.0001). Only women who developed preterm PE exhibited a high resistance-low volume haemodynamic state at mid-gestation. The latter group also had evidence of left ventricular diastolic or systolic dysfunction (33%) and segmental impaired myocardial relaxation (72%). CONCLUSIONS: Asymptomatic cardiac diastolic dysfunction is evident at mid-gestation in women who subsequently develop preterm PE but not in those who develop term PE. These cardiac findings are useful in understanding the pathophysiology of PE and corroborate the concept that PE is not a single disorder, but a cluster of symptoms that have several different aetiologies.

Prevalence of maternal cardiac defects in women with high-resistance uterine artery Doppler indices.

OBJECTIVES: To compare the prevalence of previously undiagnosed cardiac structural abnormalities in pregnant women with normal- and high-resistance midtrimester uterine artery Doppler indices. METHODS: Maternal transthoracic echocardiography was undertaken in asymptomatic pregnant women after uterine artery Doppler screening for pre-eclampsia at 21-23 weeks' gestation. Women with a mean uterine artery pulsatility index above the 90(th) centile (1.25) for the local population (multiethnic, socially diverse and migrant) were considered to have high-resistance uteroplacental blood flow indices. The prevalence of newly diagnosed cardiac structural defects in these women was recorded. RESULTS: A total of 491 women underwent echocardiography, of whom 205 had high-resistance uterine artery blood flow indices. There were nine previously undiagnosed, functionally significant cardiac defects in the high-resistance uterine artery blood flow group and only one, functionally insignificant cardiac defect in the normal-resistance group (P = 0.005; relative risk = 12.6, 95% confidence interval, 1.60-98.34). Multiple regression analysis demonstrated that both uterine artery Doppler indices (P = 0.024) and ethnicity (P = 0.048) contributed independently towards a higher prevalence of cardiac defects. CONCLUSIONS: The prevalence of previously undiagnosed maternal cardiac structural abnormalities is significantly increased in women with high midtrimester uterine artery Doppler resistance indices. This observation has important consequences for the current and long-term medical care provided to these patients. Detailed maternal cardiac assessment with echocardiography may be required in migrant women with high uterine artery Doppler indices.

Counseling in isolated mild fetal ventriculomegaly.

In this Review we aim to provide up-to-date and evidence-based answers to the common questions regarding the diagnosis of isolated mild fetal ventriculomegaly (VM). A literature search was performed to identify all reports of antenatal VM in the English language literature. In addition, reference lists of articles identified using the search were scrutinized to further identify relevant articles. Fetal mild VM is commonly defined as a ventricular atrial width of 10.0-15.0 mm, and it is considered isolated if there are no associated ultrasound abnormalities. There is no good evidence to suggest that the width of the ventricular atria contributes to the risk of neurodevelopmental outcome in fetuses with mild VM. The most important prognostic factors are the association with other abnormalities that escape early detection and the progression of ventricular dilatation, which are reported to occur in about 13% and 16% of cases, respectively. Most infants with a prenatal diagnosis of isolated mild VM have normal neurological development at least in infancy. The rate of abnormal or delayed neurodevelopment in infancy is about 11%, and it is unclear whether this is higher than in the general population. Furthermore, the number of infants that develop a real handicap is unknown. There are limitations of existing studies of mild VM. Although they address many of the relevant questions regarding the prognosis and management of fetal isolated mild VM, there is a lack of good-quality postnatal follow-up studies. The resulting uncertainties make antenatal counseling for this abnormality difficult.

First-trimester uterine artery Doppler indices in the prediction of small-for-gestational age pregnancy and intrauterine growth restriction.

OBJECTIVES: To assess the relationship of first-trimester uterine artery Doppler indices with subsequent delivery of small-for-gestational age (SGA) neonates or intrauterine growth restriction (IUGR). METHODS: This was a prospective study in which uterine artery Doppler assessment was performed at 11-14 weeks in 3010 women with singleton pregnancies. Resistance indices (RI) and incidence of bilateral notching were compared between women with normal pregnancies (n = 2445) and those who delivered: SGA neonates (birth weight < 10th centile) (n = 377); SGA neonates who had been affected by pre-eclampsia (n = 27); IUGR neonates (birth weight < 10th centile and abnormal Doppler indices) with delivery > or = 37 weeks (n = 62); and IUGR neonates requiring preterm delivery (delivery < 37 weeks) (n = 36). RESULTS: The first-trimester uterine artery mean RI and prevalence of bilateral notching were significantly higher in women destined to deliver SGA neonates than in women with normal pregnancies (median uterine artery RI, 0.74 vs. 0.70, P < 0.001; prevalence of bilateral notches, 56% vs. 43%, P < 0.001). The areas under the receiver-operating characteristics curves for the prediction of SGA without pre-eclampsia, IUGR, preterm IUGR and SGA with pre-eclampsia were 0.602, 0.687, 0.776 and 0.708, respectively. There was a statistically significant inverse relationship between mean uterine artery RI and gestational age at delivery in the SGA pregnancies without pre-eclampsia (R = - 0.329, P = 0.01). CONCLUSIONS: There is a significant relationship between first-trimester uterine artery Doppler RI and the subsequent development of SGA. The sensitivity of first-trimester uterine artery Doppler is greater for SGA with pre-eclampsia than it is for IUGR alone. This could be because these two entities may have different underlying placental abnormalities that are detected variably on first-trimester uterine artery Doppler evaluation.

First-trimester uterine artery Doppler indices in term and preterm pre-eclampsia.

OBJECTIVES: To assess the relationship between first-trimester uterine artery Doppler measurements and the development of term and preterm pre-eclampsia. METHODS: This prospective study of uterine artery Doppler findings at 11-14 weeks in 3058 singleton pregnancies included 57 and 33 cases of term and preterm pre-eclampsia, respectively. RESULTS: The first-trimester uterine artery resistance index (RI) was significantly higher in women who subsequently developed preterm pre-eclampsia (mean RI, 0.79) than in those with a normal outcome (mean RI, 0.70; P = 0.0001) or those who developed pre-eclampsia at term (mean RI, 0.72; P = 0.002). There were no significant differences in first-trimester mean uterine artery RI (P = 0.136) or prevalence of bilateral notches (P = 0.459) between women who had a normal pregnancy outcome and those who developed pre-eclampsia at term. The receiver-operating characteristics curves for the prediction of term and preterm pre-eclampsia by uterine artery Doppler imaging demonstrated a significant association with development of preterm pre-eclampsia (P = 0.0001; area under the curve (AUC), 0.76; 95% CI, 0.66-0.86) but not term pre-eclampsia (P = 0.25; AUC, 0.54; 95% CI, 0.46-0.63). CONCLUSIONS: The uterine artery Doppler data in this study suggest that preterm pre-eclampsia is strongly associated with defective invasion of the spiral arteries, in contrast to the findings in term pre-eclampsia which may be a consequence of placental deterioration at term. Our study findings support, but do not prove, a rigid separation between the etiology of early- and late-onset pre-eclampsia. Although there is a strong relationship between first-trimester uterine artery Doppler indices and the subsequent development of preterm pre-eclampsia, our data do not support its routine introduction into clinical practice.