Maternal cardiac function in fetal growth restriction

Preeclampsia and neonatal outcomes in pregnancies with maternal congenital heart disease: A nationwide cohort study from Norway

INTRODUCTION

The prevalence of congenital heart disease (CHD) among women of reproductive age is rising. We aimed to investigate the risk of preeclampsia and adverse neonatal outcomes in pregnancies of mothers with CHD compared to pregnancies of mothers without heart disease.

MATERIAL AND METHODS

In a nationwide cohort of pregnancies in Norway 1994-2014, we retrieved information on maternal heart disease, the course of pregnancy, and neonatal outcomes from national registries. Comparing pregnancies with maternal CHD to pregnancies without maternal heart disease, we used Cox regression to estimate the adjusted hazard ratio (aHR) for preeclampsia and log-binomial regression to estimate the adjusted risk ratio (aRR) for adverse neonatal outcomes. The estimates were adjusted for maternal age and year of childbirth and presented with 95% confidence intervals (CIs).

RESULTS

Among 1 218 452 pregnancies, 2425 had mild maternal CHD, and 603 had moderate/severe CHD. Compared to pregnancies without maternal heart disease, the risk of preeclampsia was increased in pregnancies with mild and moderate/severe maternal CHD (aHR1.37, 95% CI 1.14-1.65 and aHR 1.62, 95% CI 1.13-2.32). The risk of preterm birth was increased in pregnancies with mild maternal CHD (aRR 1.33, 95% CI 1.15-1.54) and further increased with moderate/severe CHD (aRR 2.49, 95% CI 2.03-3.07). Maternal CHD was associated with elevated risks of both spontaneous and iatrogenic preterm birth. The risk of infants small-for-gestational-age was slightly increased with mild maternal CHD (aRR 1.12, 95% CI 1.00-1.26) and increased with moderate/severe CHD (aRR 1.63, 95% CI 1.36-1.95). The prevalence of stillbirth was 3.9 per 1000 pregnancies without maternal heart disease, 5.6 per 1000 with mild maternal CHD, and 6.8 per 1000 with moderate/severe maternal CHD. Still, there were too few cases to report a significant difference. There were no maternal deaths in women with CHD.

CONCLUSIONS

Moderate/severe maternal CHD in pregnancy was associated with increased risks of preeclampsia, preterm birth, and infants small-for-gestational-age. Mild maternal CHD was associated with less increased risks. For women with moderate/severe CHD, their risk of preeclampsia and adverse neonatal outcomes should be evaluated together with their cardiac risk in pregnancy, and follow-up in pregnancy should be ascertained.

Perinatal outcomes in pregnancies complicated by maternal cardiomyopathy: a systematic review and meta-analysis

OBJECTIVE

This study aimed to systematically assess perinatal outcomes of pregnancies complicated by maternal cardiomyopathy.

DATA SOURCES

PubMed, Ovid Embase, Ovid MEDLINE, the Cochrane Library, and ClinicalTrials.gov were systematically searched from inception to August 25, 2022.

STUDY ELIGIBILITY CRITERIA

Observational cohort, case-control, and case-cohort studies in human populations were included if they reported predefined perinatal outcomes in pregnant women with cardiomyopathy (any subtype) and an appropriate control population (either pregnant women with no known cardiac disease or pregnant women with noncardiomyopathy cardiac disease).

METHODS

Of note, 2 reviewers independently assessed the articles for eligibility and risk of bias, and conflicts were resolved by a third reviewer. Data were extracted and synthesized according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis of Observational Studies in Epidemiology guidelines.

RESULTS

Here, 13 studies (representing 2,291,024 pregnancies) were eligible for inclusion. Perinatal death was more likely in neonates born to women with cardiomyopathy than in (1) neonates born to women with no cardiac disease (stillbirth: odds ratio, 20.82; 95% confidence interval, 6.68-64.95; I² = not available; P<.00001; neonatal mortality: odds ratio, 6.75; 95% confidence interval, 3.54-12.89; I²=0%; P<.00001) and (2) neonates born to women with other forms of cardiac disease (stillbirth: odds ratio, 3.75; 95% confidence interval, 1.86-7.59; I²=0%; P=.0002; neonatal mortality: odds ratio, 2.42; 95% confidence interval, 1.39-4.21; I²=0%; P=.002). Pregnancies affected by maternal cardiomyopathy were significantly more likely to result in preterm birth (odds ratio, 2.21; 95% confidence interval, 1.31-3.73; I²=77%; P=.003) and small-for-gestational-age neonates (odds ratio, 2.97; 95% confidence interval, 2.38-3.70; I²=47%; P<.00001), both major causes of short- and long-term morbidities, than pregnancies affected by other forms of cardiac disease.

CONCLUSION

There was an increased likelihood of adverse perinatal outcomes in pregnancies affected by maternal cardiomyopathy compared with both pregnancies affected by noncardiomyopathy cardiac disease and pregnancies without cardiac disease. Women with cardiomyopathy who plan to get pregnant should receive detailed counseling regarding these risks and have their pregnancies managed by experienced multidisciplinary teams that can provide close fetal monitoring and neonatology expertise.

Maternal Low Volume Circulation Relates to Normotensive and Preeclamptic Fetal Growth Restriction

This narrative review summarizes current evidence on the association between maternal low volume circulation and poor fetal growth. Though much work has been devoted to the study of cardiac output and peripheral vascular resistance, a low intravascular volume may explain why high vascular resistance causes hypertension in women with preeclampsia (PE) that is associated with fetal growth restriction (FGR) and, at the same time, presents with normotension in FGR itself. Normotensive women with small for gestational age babies show normal gestational blood volume expansion superimposed upon a constitutionally low intravascular volume. Early onset preeclampsia (EPE; occurring before 32 weeks) is commonly associated with FGR, and poor plasma volume expandability may already be present before conception, thus preceding gestational volume expansion. Experimentally induced low plasma volume in rodents predisposes to poor fetal growth and interventions that enhance plasma volume expansion in FGR have shown beneficial effects on intrauterine fetal condition, prolongation of gestation and birth weight. This review makes the case for elevating the maternal intravascular volume with physical exercise with or without Nitric Oxide Donors in FGR and EPE, and evaluating its role as a potential target for prevention and/or management of these conditions.

Maternal left ventricular function and adverse neonatal outcomes in women with cardiac disease

Purpose

To evaluate the relationship between maternal left ventricular systolic function, utero-placental circulation, and risk of adverse neonatal outcomes in women with cardiac disease.

Methods

119 women managed in the pregnancy heart clinic (2019–2021) were identified. Women were classified by their primary cardiac condition. Adverse neonatal outcomes were: low birth weight (< 2500 g), small-for-gestational-age (< 10th birth-weight centile), pre-term delivery (< 37 weeks’ gestation), and fetal demise (> 20 weeks’ gestation). Parameters of left ventricular systolic function (global longitudinal strain, radial strain, ejection fraction, average S’, and cardiac output) were calculated and pulsatility index was recorded from last growth scan.

Results

Adverse neonatal outcomes occurred in 28 neonates (24%); most frequently in valvular heart disease (n = 8) and cardiomyopathy (n = 7). Small-for-gestational-age neonates were most common in women with cardiomyopathy (p = 0.016). Early pregnancy average S’ (p = 0.03), late pregnancy average S’ (p = 0.02), and late pregnancy cardiac output (p = 0.008) were significantly lower in women with adverse neonatal outcomes than in those with healthy neonates. There was a significant association between neonatal birth-weight centile and global longitudinal strain (p = 0.04) and cardiac output (p = 0.0002) in late pregnancy. Pulsatility index was highest in women with cardiomyopathy (p = 0.007), and correlated with average S’ (p < 0.0001) and global longitudinal strain (p = 0.03) in late pregnancy.

Conclusion

Women with cardiac disease may not tolerate cardiovascular adaptations required during pregnancy to support fetal growth. Adverse neonatal outcomes were associated with reduced left ventricular systolic function and higher pulsatility index. The association between impaired systolic function and reduced fetal growth is supported by insufficient utero-placental circulation.

Cardiovascular Disease in Pregnancy

Cardiovascular disease remains a major contributor to rising maternal morbidity and mortality. Both the pregnant woman and fetus are exposed to many potential complications as a result of the physiologic changes of pregnancy. These changes can exacerbate existing cardiac disease, as well as lead to the development of de novo issues during gestation, delivery, and the postnatal period. For women with preexisting cardiac disease, including congenital malformations, valvular disease, coronary artery disease, and aortopathies, it is crucial that they receive multidisciplinary evaluation, counseling, and optimization before conception, as well as close monitoring and medication management during pregnancy. Close monitoring is also essential for patients who develop cardiovascular complications such as preeclampsia, cardiomyopathy, congestive heart failure, coronary events, and arrhythmias during pregnancy. In addition, concerning disparities in maternal morbidity and mortality exist across many dimensions, in part because of the lack of uniformity of care in different treatment settings. Establishment of multidisciplinary cardio-obstetric teams including representatives from cardiology, anesthesia, obstetrics, maternal-fetal medicine, and specialized nursing has proven instrumental to delivering evidence-based and equitable care to high-risk patients. Multidisciplinary teams should work to guide these patients through the preconception, antepartum, delivery, and postpartum phases to ensure appropriate care for weeks to years after pregnancy.

Maternal and Fetal Hemodynamic Adaptations to Pregnancy and Clinical Outcomes in Maternal Cardiac Disease

BACKGROUND

Although insufficient maternal cardiac output (CO) has been implicated in poor outcomes in mothers with heart disease (HD), maternal-fetal interactions remain incompletely understood. We sought to quantify maternal-fetal hemodynamics using magnetic resonance imaging (MRI) and explore their relationships with adverse events.

METHODS

Pregnant women with moderate or severe HD (n=22; age 32±5 years) were compared with healthy controls (n=21; 34±3 years). An MRI was performed during the third trimester at peak output (maternal-fetal) and six-months postpartum with return of maternal hemodynamics to baseline (reference). Phase-contrast MRI was used for flow quantification and was combined with T1/T2 relaxometry for derivation of fetal oxygen delivery/consumption.

RESULTS

 Third trimester CO and cardiac index (CI) measurements were similar in HD and control groups (CO 7.2±1.5 versus 7.3±1.6 L/min, p=0.79; CI 4.0±0.7 versus 4.3±0.7 L/min/m², p=0.28). However, the magnitude of CO/CI increase (Δ, peak-pregnancy-reference) in the HD group exceeded controls (CO 46±24% versus 27±16%, p=0.007; CI 51±28% versus 28±17%, p=0.005). Fetal growth and oxygen delivery/consumption were similar between groups. Adverse cardiovascular outcomes (non-mutually exclusive) in 6 HD women included arrhythmia (n=4), heart failure (n=2) and hypertensive disorder of pregnancy (n=1); fetal prematurity was observed in 2 of these women. The odds of a maternal cardiovascular event were inversely associated with peak CI (OR 0.10 [95% confidence interval 0.001-0.86], p=0.04) and ΔCI (0.02 [0.001-0.71], p=0.03).

CONCLUSIONS

 Maternal-fetal hemodynamics can be well-characterized in pregnancy using MRI. Impaired adaptation to pregnancy in women with HD appears to be associated with development of adverse outcomes of pregnancy.

BRIEF SUMMARY

Maternal and placental-fetal vascular flows in women with heart disease (HD) were measured using magnetic resonance imaging. Adaptive peak pregnancy cardiac output and cardiac index (CI) were formidable in the majority of mothers. Placental-fetal hemodynamics were maintained and neonatal outcomes were favourable. Women with adverse cardiovascular events in pregnancy had insufficient augmentation of CI antenatally. Understanding hemodynamic responses of HD mothers in pregnancy may help physicians counsel women pre-conceptually and further optimize management antenatally.

Maternal cardiac adaptation and fetal growth

BACKGROUND

Pregnancies with small-for-gestational-age fetuses are at increased risk of adverse maternal-fetal outcomes. Previous studies examining the relationship between maternal hemodynamics and fetal growth were mainly focused on high-risk pregnancies and those with fetuses with extreme birthweights, such as less than the 3rd or 10th percentile and assumed a similar growth pattern in fetuses above the 10th percentile throughout gestation.

OBJECTIVE

This study aimed to evaluate the trends in maternal cardiac function, fetal growth, and oxygenation with advancing gestational age in a routine obstetrical population and all ranges of birthweight percentiles.

STUDY DESIGN

This was a prospective, longitudinal study assessing maternal cardiac output and peripheral vascular resistance by bioreactance at 11⁺⁰ to 13⁺⁶, 19⁺⁰ to 24⁺⁰, 30⁺⁰ to 34⁺⁰, and 35⁺⁰ to 37⁺⁰ weeks' gestation, sonographic estimated fetal weight in the last 3 visits and the ratio of the middle cerebral artery by umbilical artery pulsatility indices or cerebroplacental ratio in the last 2 visits. Women were divided into the following 5 groups according to birthweight percentile: group 1, <10th percentile (n=261); group 2, 10 to 19.9 percentile (n=180); group 3, 20 to 29.9 percentile (n=189); group 4, 30 to 69.9 percentile (n=651); and group 5, ≥70th percentile (n=508). The multilevel linear mixed-effects model was performed to compare the repeated measures of hemodynamic variables and z scores of the estimated fetal weight and cerebroplacental ratio.

RESULTS

In visit 2, compared with visit 1, in all groups, cardiac output increased, and peripheral vascular resistance decreased. At visit 3, groups 1, 2, and 3, compared with 4 and 5, demonstrated an abrupt decrease in cardiac output and increase in peripheral vascular resistance. From visit 2, group 1 had a constant decline in estimated fetal weight, coinciding with the steepest decline in maternal cardiac output and rise in peripheral vascular resistance. In contrast, in groups 4 and 5, the estimated fetal weight had a stable or accelerative pattern, coinciding with the greatest increase in cardiac output and lowest peripheral vascular resistance. Groups 2 and 3 showed a stable growth pattern with intermediate cardiac output and peripheral vascular resistance. Increasing birthweight was associated with higher cerebroplacental ratio. Groups 3, 4, and 5 had stable cerebroplacental ratio across visits 3 and 4, whereas groups 1 and 2 demonstrated a significant decline (P<.001).

CONCLUSION

In a general obstetrical population, maternal cardiac adaptation at 32 weeks' gestation parallels the pattern of fetal growth and oxygenation; babies with birthweight<20th percentile have progressive decline in fetal cerebroplacental ratio, decline in maternal cardiac output, and increase in peripheral vascular resistance.

Clinical validation of bioreactance for the measurement of cardiac output in pregnancy

Maternal cardiac dysfunction is associated with pre-eclampsia, fetal growth restriction and haemodynamic instability during obstetric anaesthesia. There is growing interest in the use of non-invasive cardiac output monitoring to guide antihypertensive and fluid therapies in obstetrics. The aim of this study was to validate thoracic bioreactance using the NICOM® instrument against transthoracic echocardiography in pregnant women, and to assess the effects of maternal characteristics on the absolute difference of stroke volume, cardiac output and heart rate. We performed a prospective study involving women with singleton pregnancies in each trimester. We recruited 56 women who were between 11 and 14 weeks gestation, 57 between 20 and 23 weeks, and 53 between 35 and 37 weeks. Cardiac output was assessed repeatedly and simultaneously over 5 min in the left lateral position with NICOM and echocardiography. The performance of NICOM was assessed by calculating bias, 95% limits of agreement and mean percentage difference relative to echocardiography. Multivariate regression analysis evaluated the effect of maternal characteristics on the absolute difference between echocardiography and NICOM. The mean percentage difference of cardiac output measurements between the two methods was ±17%, with mean bias of -0.13 l.min^-1 and limits of agreement of -1.1 to 0.84; stroke volume measurements had a mean percentage difference of ±15%, with a mean bias of -0.8 ml (-10.9 to 12.6); and heart rate measurements had a mean percentage difference of ±6%, with a mean bias of -2.4 beats.min^-1 (-6.9 to 2.0). Similar results were found when the analyses were confined to each individual trimester. The absolute difference between NICOM and echocardiography was not affected by maternal age, weight, height, race, systolic or diastolic blood pressure. In conclusion, NICOM demonstrated good agreement with echocardiography, and can be used in pregnancy for the measurement of cardiac function.

Are maternal hemodynamic indices markers of fetal growth restriction in pregnancies with a small-for-gestational-age fetus?

OBJECTIVE

Pregnancies complicated by fetal growth restriction (FGR) have a worse outcome than those with a small-for-gestational-age (SGA) fetus. There is increasing evidence of a maternal cardiovascular role in the pathophysiology of FGR. We aimed to compare maternal hemodynamic indices between pregnancies complicated by FGR and those delivering a SGA neonate, using a non-invasive device.

METHODS

This was a prospective study of normotensive pregnancies complicated by FGR (defined as estimated fetal weight (EFW) < 3^rd centile or Doppler evidence of impaired placental-fetal blood flow), those with a SGA fetus (defined as EFW < 10^th centile) and control pregnancies with an appropriately grown fetus. Assessment of maternal hemodynamics (heart rate (HR), cardiac output (CO), mean arterial pressure (MAP), systemic vascular resistance (SVR) and stroke volume) was performed using a non-invasive device (USCOM-1A®). Uterine artery (UtA) pulsatility index (PI) was measured using transabdominal ultrasound. Hemodynamic variables that are affected by gestational age and maternal characteristics were corrected for using device-specific reference ranges. Comparison between groups was performed using the chi-square test or the Mann-Whitney U-test, as appropriate.

RESULTS

A total of 102 FGR, 64 SGA and 401 control pregnancies, with a median gestational age of 36 weeks, were included in the analysis. Women with a pregnancy complicated by FGR and those with a SGA fetus were shorter and weighed less than did controls. Compared with controls, the FGR group had significantly lower median maternal HR (80 beats per min (bpm) vs 85 bpm; P = 0.001) and CO multiples of the median (MoM; 0.91 vs 0.98; P = 0.003), and higher median maternal MAP (90 mmHg vs 87 mmHg; P = 0.040), SVR MoM (1.2 vs 1.0; P < 0.001) and UtA-PI MoM (1.1 vs 0.96; P < 0.001), but there was no significant difference in stroke volume MoM (1.0 vs 0.98; P = 0.647). Compared with the SGA group, the FGR group had a significantly lower median HR (80 bpm vs 87 bpm; P = 0.022), and higher median maternal MAP (90 mmHg vs 85 mmHg; P = 0.025), SVR MoM (1.2 vs 1.0; P = 0.002) and UtA-PI MoM (1.1 vs 0.98; P = 0.005), but there was no significant difference in CO MoM (0.91 vs 0.96; P = 0.092) or stroke volume MoM (1.0 vs 1.0; P = 0.806). There were no significant differences in adjusted maternal hemodynamic indices between the SGA group and controls.

CONCLUSION

Pregnancies complicated by FGR presented with impaired maternal hemodynamic function, as evidenced by lower HR and CO, as well as higher MAP, SVR and UtA resistance. Pregnancies delivering a SGA neonate, without evidence of FGR, had normal maternal hemodynamic function. Maternal hemodynamic indices may therefore be of value in distinguishing FGR from SGA pregnancies. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Effect of sildenafil on maternal hemodynamics in pregnancies complicated by severe early-onset fetal growth restriction: planned subgroup analysis from a multicenter randomized placebo-controlled double-blind trial

OBJECTIVES

Fetal growth restriction (FGR) is associated with maternal cardiovascular changes. Sildenafil, a phosphodiesterase type-5 inhibitor, potentiates the actions of nitric oxide, and it has been suggested that it alters maternal hemodynamics, potentially improving placental perfusion. Recently, the Dutch STRIDER trial was stopped prematurely owing to excess neonatal mortality secondary to pulmonary hypertension. The main aim of this study was to investigate the effect of sildenafil on maternal hemodynamics in pregnancies with severe early-onset FGR.

METHODS

This was a cardiovascular substudy within a UK multicenter, placebo-controlled trial, in which 135 women with a singleton pregnancy and severe early-onset FGR (defined as a combination of estimated fetal weight or abdominal circumference below the 10^th centile and absent/reversed end-diastolic flow in the umbilical artery on Doppler velocimetry, diagnosed between 22 + 0 and 29 + 6 weeks' gestation) were assigned randomly to receive either 25 mg sildenafil three times daily or placebo until 32 + 0 weeks' gestation or delivery. Maternal blood pressure (BP), heart rate (HR), augmentation index, pulse wave velocity (PWV), cardiac output, stroke volume (SV) and total peripheral resistance were recorded before randomization, 1-2 h and 48-72 h post-randomization, and 24-48 h postnatally. For continuous data, analysis was performed using repeated measures ANOVA methods including terms for timepoint, treatment allocation and their interaction.

RESULTS

Included were 134 women assigned randomly to sildenafil (n = 69) or placebo (n = 65) who had maternal BP and HR recorded at baseline. At 1-2 h post-randomization, compared with baseline values, sildenafil increased maternal HR by 4 bpm more than did placebo (mean difference, 5.00 bpm (95% CI, 1.00-12.00 bpm) vs 1.25 bpm (95% CI, -5.38 to 7.88 bpm); P = 0.004) and reduced systolic BP by 1 mmHg more (mean difference, -4.13 mmHg (95% CI, -9.94 to 1.44 mmHg) vs -2.75 mmHg (95% CI, -7.50 to 5.25 mmHg); P = 0.048). Even after adjusting for maternal mean arterial pressure, sildenafil reduced aortic PWV by 0.60 m/s more than did placebo (mean difference, -0.90 m/s (95% CI, -1.31 to -0.51 m/s) vs -0.26 m/s (95% CI, -0.75 to 0.59 m/s); P = 0.001). Sildenafil was associated with a non-significantly greater decrease in SV index after 1-2 h post-randomization than was placebo (mean difference, -5.50 mL/m² (95% CI, -11.00 to -0.50 mL/m² ) vs 0.00 mL/m² (95% CI, -5.00 to 4.00 mL/m² ); P = 0.056).

CONCLUSIONS

Sildenafil in a dose of 25 mg three times daily increases HR, reduces BP and reduces arterial stiffness in pregnancies complicated by severe early-onset FGR. These changes are short term, modest and consistent with the anticipated vasodilatory effect. They have no short- or long-term clinical impact on the mother. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Study protocol for a prospective cohort study to investigate Hemodynamic Adaptation to Pregnancy and Placenta-related Outcome: the HAPPO study

INTRODUCTION

The importance of cardiovascular health in relation to pregnancy outcome is increasingly acknowledged. Women who develop certain pregnancy complications, in particular preeclampsia, are at higher risk for future cardiovascular disease. Independent of its outcome, pregnancy requires a substantial adaptive response of the maternal cardiovascular system. In the Hemodynamic Adaptation to Pregnancy and Placenta-related Outcome (HAPPO) study, we aim to examine longitudinal maternal haemodynamic adaptation to pregnancy from the preconception period onwards. We hypothesise that women who will develop adverse pregnancy outcomes have impaired cardiovascular health before conception, leading to haemodynamic maladaptation to pregnancy and diminished uteroplacental vascular development.

METHODS AND ANALYSIS

In this prospective cohort study embedded in the Rotterdam periconception cohort, 200 women with a history of placenta-related pregnancy complications (high-risk group) and 100 women with an uncomplicated obstetric history (low-risk group) will be included. At five moments (preconception, first, second and third trimester and postdelivery), women will undergo an extensive examination of the macrocirculatory and microcirculatory system and uteroplacental vascular development. The main outcome measures are differences in maternal haemodynamic adaptation to pregnancy between women with and without placenta-related pregnancy complications. In a multivariate linear mixed model, the relationship between maternal haemodynamic adaptive parameters, (utero)placental vascularisation indices and clinical outcomes (occurrence of pregnancy complications, embryonic and fetal growth trajectories, miscarriage rate, gestational age at delivery, birth weight) will be studied. Subgroup analysis will be performed to study baseline and trajectory differences between high-risk and low-risk women, independent of subsequent pregnancy outcome.

ETHICS AND DISSEMINATION

This study protocol was approved by the Medical Ethics Committee of the Erasmus MC, Rotterdam, the Netherlands (MEC 2018-150). Results will be disseminated to the medical community by publications in peer-reviewed journals and presentations at scientific congresses. Also, patient associations will be informed and the public will be informed by dissemination through (social) media.

TRIAL REGISTRATION NUMBER

NL7394 (www.trialregister.nl).

The effect of parity on longitudinal maternal hemodynamics

BACKGROUND

Parous women have a lower risk for pregnancy complications, such as preeclampsia or delivery of small-for-gestational-age neonates. However, parous women are a heterogeneous group of patients because they contain a low-risk cohort with previously uncomplicated pregnancies and a high-risk cohort with previous pregnancies complicated by preeclampsia and/or small for gestational age. Previous studies examining the effect of parity on maternal hemodynamics, including cardiac output and peripheral vascular resistance, did not distinguish between parous women with and without a history of preeclampsia or small for gestational age and reported contradictory results.

OBJECTIVE

The objective of the study was to compare maternal hemodynamics in nulliparous women and in parous women with and without previous preeclampsia and/or small for gestational age.

STUDY DESIGN

This was a prospective, longitudinal study of maternal hemodynamics, assessed by a bioreactance method, measured at 11⁺⁰ to 13⁺⁶, 19⁺⁰ to 24⁺⁰, 30⁺⁰ to 34⁺⁰, and 35⁺⁰ to 37⁺⁰ weeks' gestation in 3 groups of women. Group 1 was composed of parous women without a history of preeclampsia and/or small for gestational age (n = 632), group 2 was composed of nulliparous women (n = 829), and group 3 was composed of parous women with a history of preeclampsia and/or small for gestational age (n = 113). A multilevel linear mixed-effects model was performed to compare the repeated measures of hemodynamic variables controlling for maternal characteristics, medical history, and development of preeclampsia or small for gestational age in the current pregnancy.

RESULTS

In groups 1 and 2, cardiac output increased with gestational age to a peak at 32 weeks and peripheral vascular resistance showed a reversed pattern with its nadir at 32 weeks; in group 1, compared with group 2, there was better cardiac adaptation, reflected in higher cardiac output and lower peripheral vascular resistance. In group 3 there was a hyperdynamic profile of higher cardiac output and lower peripheral vascular resistance at the first trimester followed by an earlier sharp decline of cardiac output and increase of peripheral vascular resistance from midgestation. The incidence of preeclampsia and small for gestational age was highest in group 3 and lowest in group 1.

CONCLUSION

There are parity-specific differences in maternal cardiac adaptation in pregnancy.

Restricted physical activity in pregnancy reduces maternal vascular resistance and improves fetal growth

OBJECTIVES

To test the efficacy of maternal activity restriction for reducing peripheral vascular resistance in normotensive pregnant women with raised total vascular resistance (TVR) and to evaluate its effect on fetal growth.

METHODS

This was a prospective case-control study of 30 women enrolled between 27 and 29 weeks' gestation. All patients met the following criteria: normal blood pressure before and during pregnancy, TVR between 1300 and 1400 dynes × s/cm⁵ at enrolment, normal fetal Doppler parameters at enrolment and abdominal circumference between the 10^th and 25^th centiles. Patients were assigned to activity restriction (activity-restriction group; n = 15) or no treatment (control group; n = 15) and were assessed after 4 weeks for TVR and fetal growth.

RESULTS

TVR at enrolment and estimated fetal weight centile were similar in the activity-restriction group vs controls (1358 ± 26 vs 1353 ± 30 dynes × s/cm⁵ ; 18^th  ± 4 vs 19^th  ± 4 centile; P = NS). After 4 weeks, the activity-restriction group compared with controls showed significantly lower TVR (1165 ± 159 vs 1314 ± 190 dynes × s/cm⁵ ; P < 0.05), which was associated with higher estimated fetal weight centile (25^th  ± 5 vs 20^th  ± 5 centile; P < 0.05). TVR was lower and estimated fetal weight centile higher for the activity-restriction group after 4 weeks compared with at enrolment.

CONCLUSIONS

In normotensive pregnant women with raised TVR, maternal activity restriction appears to be effective in reducing TVR and therefore enhancing fetal growth. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Pregnant women with heart disease: Placental characteristics and their association with fetal adverse events

BACKGROUND

Pregnant women with heart disease (HD) have higher rates of adverse fetal outcomes. We describe placental pathologic characteristics and their association with fetal events.

METHODS

In pregnant women, known HD were categorized into: (1) cardiomyopathy (CM) or (2) other HD (congenital, coronary, arrhythmia, or valvular). Outcomes were maternal major adverse cardiac events (MACE), fetal adverse clinical events (FACE), a composite of infant death, prematurity, underweight status, intracranial hemorrhage, and respiratory distress. Only pathologically reported placental analyses were included.

RESULTS

We studied 86 pregnancies in women with CM and HD, with pathologic analyses on 35 CM and 52 HD placentas. CM placentas, compared with those with HD, were more likely to have ischemic changes (65.7% vs. 37%, p 0.008), demonstrate immaturity (62.90% vs. 10%, p < 0.001), and have a lower weight (p < 0.001), despite similar gestational age. CM was independently associated with increased risk for MACE (OR 7.38, 95%CI 2.20-24.76). Ischemic placental changes were associated with increased odds of FACE (OR 24.78, 95%CI 2.37-259.03).

CONCLUSIONS

Women with CM were more likely to have ischemic placentas, with lower placental and fetal weights, and evidence of immaturity compared with those with other forms of HD, and an increased odds of MACE.

Echocardiographic Techniques of Deformation Imaging in the Evaluation of Maternal Cardiovascular System in Patients with Complicated Pregnancies

Cardiovascular diseases (CVD) represent the leading cause of maternal mortality and morbidity. Knowledge of CVD in women is constantly evolving and data are emerging that female-specific risk factors as complications of pregnancy are conditions associated with an increased risk for the long-term development of CVD. Echocardiography is a safe and effective imaging technique indicated in symptomatic or asymptomatic pregnant women with congenital heart diseases who require close monitoring of cardiac function. Deformation imaging is an echocardiographic technique used to assess myocardial function by measuring the actual deformation of the myocardium through the cardiac cycle. Speckle-tracking echocardiography (STE) is a two-dimensional (2D) technique which has been found to be more accurate than tissue Doppler to assess both left ventricular (LV) and right ventricular (RV) myocardial function. The use of 2D STE however might present some technical issues due to the tomographic nature of the technique and the motion in the three-dimensional space of the myocardial speckles. This has promoted the use of 3D STE to track the motion of the speckles in the 3D space. This review will focus on the clinical value of the new echocardiographic techniques of deformation imaging used to assess the maternal cardiovascular system in complicated pregnancies.

Mode of Delivery and Pregnancy Outcome in Women with Congenital Heart Disease

BACKGROUND

Advances in cardiac surgery and congenital cardiology have led to an increasing number of women with congenital heart disease (CHD) reaching childbearing age. In general, cardiologists recommend vaginal delivery for women with CHD to avoid complications from Caesarean section as many women with CHD tolerate vaginal delivery well.

METHODS AND RESULTS

This is a single-center study comparing mode of delivery, pregnancy outcome, indications for Caesarean section and induction of labor between women with and without CHD. A historical cohort study was conducted including 116 patients with CHD. An individual threefold matching with 348 women without CHD was carried out. Caesarean section was performed in 46.6% of pregnancies with CHD (33.6% without CHD, P = 0.012). Primary Caesarean section increases with severity of CHD (P = 0.036), 33.3% of women with CHD had primary planned Caesarean section due to cardiac reasons. Induction of labor was performed in 45.7% of attempted vaginal deliveries in women with CHD (27.9% without CHD, P = 0.001). Lower mean birth weight (P = 0.004) and Small for Gestational Age (SGA) (P < 0.001) were more common in women with CHD. One CHD patient suffered from postpartum hemorrhage.

CONCLUSIONS

Concerns about maternal deterioration resulting in higher rates of induction of labor seem unjustified in most cases. Along with a possible reduction of Caesarean section on maternal request, a reduction of planned vaginal delivery may be expedient in reducing the rate of Caesarean section in women with CHD.

Bioimpedance cardiography in pregnancy: A longitudinal cohort study on hemodynamic pattern and outcome

Background

Pregnancy associated cardiovascular pathologies have a significant impact on outcome for mother and child. Bioimpedance cardiography may provide additional outcome-relevant information early in pregnancy and may also be used as a predictive instrument for pregnancy-associated diseases.

Methods

We performed a prospective longitudinal cohort trial in an outpatient setting and included 242 pregnant women. Cardiac output and concomitant hemodynamic data were recorded from 11^th–13^th week of gestation every 5^th week as well as at two occasions post partum employing bioimpedance cardiography.

Results

Cardiac output increased during pregnancy and peaked early in the third trimester. A higher heart rate and a decreased systemic vascular resistance were accountable for the observed changes. Women who had a pregnancy-associated disease during a previous pregnancy or developed hypertension or preeclampsia had a significantly increased cardiac output early in pregnancy. Furthermore, an effect of cardiac output on birthweight was found in healthy pregnancies and could be confirmed with multiple linear regression analysis.

Conclusions

Cardiovascular adaptation during pregnancy is characterized by distinct pattern described herein. These may be altered in women at risk for preeclampsia or reduced birthweigth. The assessment of cardiac parameters by bioimpedance cardiography could be performed at low costs without additional risks.

Maternal Cardiac Output and Fetal Doppler Predict Adverse Neonatal Outcomes in Pregnant Women With Heart Disease

BACKGROUND

The mechanistic basis of the proposed relationship between maternal cardiac output and neonatal complications in pregnant women with heart disease has not been well elucidated.

METHODS AND RESULTS

Pregnant women with cardiac disease and healthy pregnant women (controls) were prospectively followed with maternal echocardiography and obstetrical ultrasound scans at baseline, third trimester, and postpartum. Fetal/neonatal complications (death, small-for-gestational-age or low birthweight, prematurity, respiratory distress syndrome, or intraventricular hemorrhage) comprised the primary study outcome. One hundred and twenty-seven women with cardiac disease and 45 healthy controls were enrolled. Neonatal events occurred in 28 pregnancies and were more frequent in the heart disease group as compared with controls (n=26/127 or 21% versus n=2/45 or 4%; P=0.01). Multiple complications in an infant were counted as a single outcome event. Neonatal complications in the heart disease group were small-for-gestational-age/low birthweight (n=18), prematurity (n=14), and intraventricular hemorrhage/respiratory distress syndrome (n=5). Preexisting obstetric risk factors (P=0.003), maternal cardiac output decline from baseline to third trimester (P=0.017), and third trimester umbilical artery Doppler abnormalities (P<0.001) independently predicted neonatal complications and were incorporated into a novel risk index in which 0, 1, and >1 predictor corresponded to expected complication rates of 5%, 30%, and 76%, respectively.

CONCLUSIONS

Decline in maternal cardiac output during pregnancy and abnormal umbilical artery Doppler flows independently predict neonatal complications. These findings will enhance the identification of higher risk pregnancies that would benefit from close antenatal surveillance.

Maternal functional hemodynamics in the second half of pregnancy: a longitudinal study

Objective

Cardiovascular response to passive leg raising (PLR) is useful in assessing preload reserve, but it has not been studied longitudinally during pregnancy. We aimed to investigate gestational age associated serial changes in maternal functional hemodynamics and establish longitudinal reference ranges for the second half of pregnancy.

Materials and Methods

This was a prospective longitudinal study on 98 healthy pregnant women who were examined 3–5 times during 20–40 weeks of gestation (a total of 441 observations). Maternal cardiac function and systemic hemodynamics were assessed at baseline and 90 seconds after PLR using impedance cardiography (ICG). The main outcome measures were gestational age specific changes in ICG-derived variables of maternal cardiovascular function and functional hemodynamic response to PLR.

Results

Hemodynamic response to PLR varied during pregnancy. PLR led to an insignificant increase in stroke volume during 20⁺⁰ to 31⁺⁶ weeks, but later in gestation the stroke volume was slightly lower at PLR compared to baseline. PLR caused no significant change in cardiac output between 20⁺⁰ and 23⁺⁶ weeks and a significant decrease after 24⁺⁰ weeks. A decrease in heart rate, mean arterial pressure, and cardiac contractility was observed during PLR throughout the second half of pregnancy. Systemic vascular resistance was reduced by PLR up to 32⁺⁰ weeks, but increased slightly thereafter.

Conclusion

Healthy pregnant women appear to have limited preload reserve and reduced cardiac contractility, especially in the third trimester, which makes them vulnerable to fluid overload and cardiac failure.

Maternal Cardiovascular Impairment in Pregnancies Complicated by Severe Fetal Growth Restriction

Fetal growth restriction and preeclampsia are both conditions of placental etiology and associated to increased risk for the long-term development of cardiovascular disease in the mother. At presentation, preeclampsia is associated with maternal global diastolic dysfunction, which is determined, at least in part, by increased afterload and myocardial stiffness. The aim of this study is to test the hypothesis that women with normotensive fetal growth-restricted pregnancies also exhibit global diastolic dysfunction. This was a prospective case-control study conducted over a 3-year period involving 29 preterm fetal growth-restricted pregnancies, 25 preeclamptic with fetal growth restriction pregnancies, and 58 matched control pregnancies. Women were assessed by conventional echocardiography and tissue Doppler imaging at diagnosis of the complication and followed-up at 12 weeks postpartum. Fetal growth-restricted pregnancies are characterized by a lower cardiac index and higher total vascular resistance index than expected for gestation. Compared with controls, fetal growth-restricted pregnancy was associated with significantly increased prevalence ( P <0.001) of asymptomatic left ventricular diastolic dysfunction (28% versus 4%) and widespread impaired myocardial relaxation (59% versus 21%). Unlike preeclampsia, cardiac geometry and intrinsic myocardial contractility were preserved in fetal growth-restricted pregnancy. Fetal growth-restricted pregnancies are characterized by a low output, high resistance circulatory state, as well as a higher prevalence of asymptomatic global diastolic dysfunction and poor cardiac reserve. These findings may explain the increased long-term cardiovascular risk in these women who have had fetal growth-restricted pregnancies. Further studies are needed to clarify the postnatal natural history of cardiac dysfunction in these women.

Relationship between cardiovascular function and fetal growth restriction in women with pre-eclampsia

OBJECTIVE

To investigate the relationship between cardiovascular function in women with pre-eclampsia and fetal growth restriction (FGR) using impedance cardiography.

METHOD

This retrospective study was performed with 639 participants allocated to one of 4 groups, a pre-eclampsia (PE) with FGR group, a PE without FGR group, a pregnancy-induced hypertension (PIH) without FGR group, and normal pregnancy (NP) group. Hemodynamic monitoring was performed noninvasively using impedance cardiography.

RESULTS

Mean arterial pressure and peripheral resistance were significantly higher, and cardiac output and maternal systolic function were significantly lower, in the 2 PE groups than in the PIH and NP groups, and these differences were the greatest between the NP and the PE with FGR groups.

CONCLUSION

Impedance cardiography allowed to observe a gradual increase in peripheral resistance and cardiac output from the NP group to the PIH, the PE without FGR, and the PE with FGR groups. The most reduced systolic function and cardiac output and the most increased peripheral resistance was observed in the PE with FGR group.

Serial hemodynamic measurement in normal pregnancy, preeclampsia, and intrauterine growth restriction

OBJECTIVE

The study hypothesis was that hemodynamic measurements in conjunction with uterine artery Doppler could enable selection of women at risk for the development of preeclampsia or fetal growth restriction.

STUDY DESIGN

Systolic (SBP) and diastolic blood pressure, heart rate (RR), cardiac output (CO), total peripheral resistance (TPR), phase difference of SBP and RR interval were measured serially before, during, and after pregnancy. At 20 weeks, uterine artery Doppler measurement was performed. Outcome was classified as preeclampsia (PE) or gestational hypertension (GH) with or without fetal growth restriction (FGR), FGR without PE or GH, and normal pregnancy (NP). Differences between these groups were assessed by 1-way analysis of variance and discriminant analysis.

RESULTS

In early pregnancy, in comparison with NP (n = 28), PE/GH had a higher SBP and phase difference of SBP-RR interval. CO was higher in PE/GH without FGR (n = 5) but not PE/GH with FGR (n = 5). FGR, either with or without PE/GH (n = 4), was associated with higher TPR. Conjunction with uterine Doppler allowed selection of 93% of women with an abnormal outcome with a specificity of 100%.

CONCLUSION

The study supports our hypothesis that in early pregnancy, hemodynamic parameters differ from normal in women predisposed to develop preeclampsia or fetal growth restriction.

Pregnancy and adult congenital heart disease

Increasing numbers of women with complex congenital heart disease are reaching childbearing age. Pregnancy is a major issue in the management of adult congenital heart disease. Cardiac disease is one of the most common causes of maternal morbidity and mortality. Complications, such as growth retardation, preterm and premature birth and even fetal and neonatal mortality, are more frequent among children of women with congenital heart disease. The risk of complications is determined by the severity of the cardiac lesion, the presence of cyanosis, the maternal functional class and the use of anticoagulation. However, the pathophysiology of these complications is not completely understood and may be related to a diminished increase in cardiac output and/or endothelial dysfunction. The management of pregnant cardiac patients is based on limited clinical information. This article reviews pre-pregnancy counseling and management during pregnancy in patients with congenital heart disease.

Maternal cardiac output between 11 and 13 weeks of gestation in the prediction of preeclampsia and small for gestational age

OBJECTIVE

To investigate maternal cardiac output in the first trimester as a predictor of preeclampsia and delivery of small for gestational age (SGA) infants.

METHODS

In women attending for routine care between 11(+0) and 13(+6) weeks of gestation, we recorded maternal variables and measured cardiac output by echocardiography. We compared cardiac output in those that developed preeclampsia (n=83), pregnancy-induced hypertension (PIH) (n=87), or SGA (n=532) with those unaffected by preeclampsia, PIH, or SGA (n=3,591). Regression analysis was used to first determine which of the factors among the maternal variables were significant predictors of cardiac output in the unaffected group and, secondly, to predict each complication by a combination of maternal variables and cardiac output.

RESULTS

In the unaffected group, cardiac output increased with gestation and maternal weight and decreased with maternal age. Cardiac output was higher in parous women, in cigarette smokers, in those taking antihypertensive or beta-mimetic medications, and in those conceiving after in vitro fertilization, and lower in women of Afro-Caribbean origin. Compared with the unaffected group, cardiac output was significantly higher in the preeclampsia and PIH groups and lower in the SGA group. In screening by cardiac output and maternal variables, for a 10% false-positive rate, the detection rates were 43.4% for all preeclampsia, 52% for preeclampsia without SGA, 23.3% for PIH, and 23.9% for SGA.

CONCLUSION

In pregnancies complicated by preeclampsia, PIH, and SGA, alterations in maternal cardiac output predate the clinical onset of the disorders by several months. Maternal cardiac output in the first trimester is increased in women who develop preeclampsia and decreased in women who deliver SGA infants.

LEVEL OF EVIDENCE

II.

Maternal cardiovascular function in pregnancies complicated by intrauterine growth restriction

OBJECTIVE

To investigate maternal cardiovascular function in pregnancies complicated by intrauterine growth restriction (IUGR).

METHODS

Maternal echocardiography and ambulatory blood pressure monitoring were performed in pregnancies complicated by IUGR (n = 12) and controls (n = 12), all of whom were normotensive at enrollment.

RESULTS

Compared to controls, maternal blood pressure (P = 0.016) and total vascular resistance (P = 0.008) were higher in IUGR pregnancies. Heart rate was lower (P = 0.003), as was systolic function expressed by midwall fractional shortening (P = 0.04). No significant differences between the two groups were observed for left atrial or left ventricular dimensions, nor for left ventricular geometry. Assessment of diastolic function by means of transmitral Doppler flow measurements revealed a significantly longer isovolumetric relaxation time in pregnancies with IUGR (P = 0.006).

CONCLUSIONS

In normotensive pregnancies complicated by IUGR, as compared to controls, there is decreased diastolic and systolic maternal cardiac function, and a higher blood pressure.