Cardiovascular Physiology of Pregnancy

Is experienced pregnancy in women with repaired tetralogy of Fallot related to diffuse myocardial fibrosis?

OBJECTIVES

To assess the impact of pregnancy on cardiac function and fibrosis by cardiovascular magnetic resonance (CMR) in patients with repaired Tetralogy of Fallot (rToF).

BACKGROUND

CMR T1 mapping can assess diffuse myocardial fibrosis which is associated to adverse clinical outcomes. Right ventricular (RV) accelerated remodeling is reported in rToF women with experienced pregnancy.

METHODS

We included rToF women from the national registry of congenital heart disease to perform CMR, assessing functional data, T1 mapping/ extracellular volume fraction (ECV). The results including clinical data were compared between women with experienced pregnancy vs non-experienced pregnancy and healthy individuals.

RESULTS

Fifty rToF women performed CMR, median age 36 (range 21-67) years. Fifteen were nulliparous. T1 mapping was compared to 30 controls, (14 women) median age 42 (24-64) years. In the left ventricle (LV), T1 times and ECV in all rToF women vs female controls were 1248 ± 61 ms/ 25.8 ± 2.9% vs 1255 ± 40 ms/ 26.8 ± 3.1%, p = 0.7 and p = 0.3, respectively. In rToF, RV T1 times was 1385 ± 124 ms and ECV 37.7 ± 5.4%. There was no association to parity or age in rToF LV T1/ ECV, p = 0.9 for both, or RV T1/ECV, p = 0.4 and p = 0.6, respectively. Indexed LV mass was higher in the rToF pregnancy group, 43 ± 10 vs 38 ± 6 g/m², p = 0.03 while RV ejection fraction was lower, 49 ± 7% vs 53 ± 6%, p = 0.04.

CONCLUSION

Women with rTOF showed evidence of increased RV CMR markers suggestive of diffuse fibrosis while LV CMR markers were within normal values. Having experienced pregnancy might affect RV function, however without association to CMR biomarkers.

The regional effect of serum hormone levels on cerebral blood flow in healthy nonpregnant women

Sex hormones estrogen (EST) and progesterone (PROG) have received increased attention for their important physiological action outside of reproduction. While studies have shown that EST and PROG have significant impacts on brain function, their impact on the cerebrovascular system in humans remains largely unknown. To address this, we used a multi-modal magnetic resonance imaging (MRI) approach to investigate the link between serum hormones in the follicular phase and luteal phase of the menstrual cycle (MC) with measures of cerebrovascular function (cerebral blood flow [CBF]) and structure (intracranial artery diameter). Fourteen naturally cycling women were recruited and assessed at two-time points of their MC. CBF was derived from pseudo-continuous arterial spin labeling while diameters of the internal carotid and basilar artery was assessed using time of flight magnetic resonance angiography, blood samples were performed after the MRI. Results show that PROG and EST had opposing and spatially distinct effects on CBF: PROG correlated negatively with CBF in anterior brain regions (r = -.86, p < .01), while EST correlations were positive, yet weak and most prominent in posterior areas (r = .78, p < .01). No significant correlations between either hormone or intracranial artery diameter were observed. These results show that EST and PROG have opposing and regionally distinct effects on CBF and that this relationship is likely not due to interactions with large intracranial arteries. Considering that CBF in healthy women appears tightly linked to their current hormonal state, future studies should consider assessing MC-related hormone fluctuations in the design of functional MRI studies in this population.

Association of pre-pregnancy body mass index and rate of weight gain during pregnancy with maternal indicators of cardiometabolic risk

BACKGROUND/OBJECTIVE

Changes in metabolism and extensive hemodynamic adjustments occur during normal pregnancy. The presence of maternal obesity imposes an overload to these physiological adaptations that may result in increased risk for the development of cardiometabolic complications during and after pregnancy. The aim of this study is to describe total cholesterol (TC), triglycerides (TG), glucose, and arterial blood pressure (BP) trajectories and to analyze the association of these cardiometabolic risk indicators during pregnancy with pre-pregnancy body mass index (pBMI) and monthly gestational weight gain (MGWG).

SUBJECTS/METHODS

A prospective cohort study of pregnant women was conducted in Mexico City. Monthly samples of blood were taken during clinical follow-up and biochemical and blood pressure were measured during each visit. Adjusted linear mixed-effect regression models were fit to describe the trajectories of these biomarkers during pregnancy and to analyze the association with pBMI and MGWG.

RESULTS

Seven hundred and twenty women were included of which 16.6% had pre-gestational obesity, 33.2% had pre-gestational overweight, 45.8% had normal pBMI and 4.4% had pre-gestational underweight. Women with pre-gestational obesity had higher lipids concentrations in the beginning of pregnancy (TC: [Formula: see text] = 33.08, p = 0.010; TG: [Formula: see text] = 31.29, p = <0.001) but the concentrations increased less than in women with normal pBMI (TC: [Formula: see text] = -14.18, p = 0.001; TG: [Formula: see text] = -5.42, p < 0.001). By the end of pregnancy, women with pre-gestational obesity had lower concentrations of lipids than women with normal pBMI. By contrast, women with pre-gestational obesity had higher glucose concentrations and higher BP levels than women with normal pBMI over pregnancy.

CONCLUSIONS

pBMI is differentially associated with longitudinal trajectories of maternal biochemical markers of cardiometabolic risk. MGWG did not significantly affect the biochemical indicators or BP trajectories. Our results suggest that pBMI is more relevant to predicting adverse cardiometabolic markers trajectories during pregnancy than MGWG.

Screening Echocardiogram in High-Risk Women with Class III Obesity to Predict the Risk of Preeclampsia

OBJECTIVE

Women with obesity and other comorbidities such as hypertension and diabetes are at an increased risk of preeclampsia and perinatal morbidity. This study evaluates whether screening echocardiogram can identify women with obesity at a higher risk of preeclampsia.

METHODS

We conducted a retrospective cohort study of women with class III obesity (body mass index [BMI] ≥40 kg/m²) and one or more medical comorbidities associated with an increased risk of preeclampsia (such as diabetes, hypertension, and rheumatologic disease) undergoing screening echocardiogram. Abnormal findings were defined as the presence of one or more of the following: diastolic dysfunction, ejection fraction of ≤45%, or cardiac chamber enlargement or hypertrophy. Multivariable logistic regression was used to estimate the odds ratio (OR) of gestational hypertension/mild preeclampsia, severe preeclampsia, and any preterm delivery <37 weeks associated with abnormal echocardiographic findings when controlling for potential confounders.

RESULTS

Of 267 eligible women, 174 (64%) underwent screening echocardiograms. Sixty-nine women (40%) had abnormal echocardiograms. Maternal clinical characteristics were similar between women with normal echocardiographic findings and women with abnormal findings. Women with abnormal echocardiograms were more likely to have chronic hypertension (78 vs. 62%, p = 0.04) and a history of preeclampsia (27 vs. 10%, p = 0.02). After controlling for confounders, women with abnormal echocardiogram were at an increased risk of hypertensive disorders of pregnancy, OR 6.80 (95% confidence interval [CI] 3.32-13.93, p = 0.01), and in particular severe preeclampsia, OR 8.77 (95% CI 3.90-19.74, p = 0.01).

CONCLUSION

Among pregnant women with class III obesity and medical comorbidities, screening echocardiogram may help identify a subset of women at the highest risk of developing preeclampsia.

KEY POINTS

· Women with obesity and comorbid conditions are at a high risk of abnormal echocardiogram.. · Women with obesity, medical comorbid conditions, and abnormal echo are at a high risk of preeclampsia.. · Screening echocardiogram can help identify obese women at the highest risk of severe preeclampsia..

Enhancement of cardiac contractility using gold-coated SU-8 cantilevers and their application to drug-induced cardiac toxicity tests

Herein, we propose an array of gold (Au)-coated SU-8 cantilevers with microgrooves for improved maturation of cardiomyocytes and describe its applications to drug-induced cardiac toxicity tests. Firstly, we evaluated the effect of cell culture substrates such as polydimethylsiloxane (PDMS), polyimide (PI), and SU-8 on the cardiomyocyte's maturation. Among these, the SU-8 with microgroove structures exhibits improved cardiomyocyte maturation. Further, thin layers of graphene and Au are coated on SU-8 substrates and the effects of these materials on cardiomyocyte maturation are evaluated by analyzing the expression of proteins such as alpha-actinin, Connexin 43 (Cx43), and Vinculin. While both conductive materials enhanced protein expression when compared to bare SU-8, the Au-coated SU-8 substrates demonstrated superior cardiomyocyte maturation. The cantilever structure is constructed using microgroove patterned SU-8 with and without an Au coating. The Au-coated SU-8 cantilever showed maximum displacement of 17.6 ± 0.3 μm on day 21 compared to bare SU-8 (14.2 ± 0.4 μm) owing to improved cardiomyocytes maturation. Verapamil and quinidine are used to characterize drug-induced changes in the contraction characteristics of cardiomyocytes on bare and Au-coated SU-8 cantilevers. The relative contraction forces and beat rates changed according to the calcium and sodium channel related drugs. Matured cardiomyocytes are less influenced by the drugs compared to immature cardiomyocytes and showed reliable IC₅₀ values. These results indicate that the proposed Au-coated SU-8 cantilever array could help improve the accuracy of toxicity screening results by allowing for the use of cardiomyocytes that have been matured on the drug screening platform.

Continuous transthoracic echocardiographic monitoring for changes in maternal cardiac hemodynamics during cesarean section under combined epidural-spinal anesthesia: a prospective, observational study

The change in maternal hemodynamics during cesarean section has not been well studied. Continuous transthoracic echocardiography can monitor cardiac function continuously. This study aimed to evaluate the effectiveness of maternal hemodynamic parameters monitoring during cesarean section using continuous transthoracic echocardiography. In this prospective, observational study, women with an uncomplicated singleton pregnancy scheduled for elective cesarean section at term under combined spinal-epidural anesthesia were enrolled. Maternal hemodynamic parameters were assessed by continuous transthoracic echocardiography at 11 pre-set time points. The image quality of continuous transthoracic echocardiography was evaluated before measurement was performed. Totally, one hundred parturients were recruited, and transthoracic echocardiography images with sufficient quality for further analysis were obtained in 72 women. Following anesthesia, maternal heart rate decreased by 11.18% and cardiac output decreased by 7.82%, but stroke volume remained stable. After delivery of the neonate and placenta, stroke volume and cardiac output increased by 21.09% and 22.33%, respectively. End-diastolic volume also increased significantly after delivery of the neonate, but end-systolic volume was unchanged. Following delivery of the neonate, fractional shortening increased till the end of the cesarean section while total peripheral resistance decreased significantly. In conclusion, continuous transthoracic echocardiographic monitoring revealed that there were significant changes in hemodynamic parameters during cesarean section after delivery of the newborn and placenta, which warranted further investigation.

Long-term follow-up and sex differences in adults operated for tetralogy of Fallot

OBJECTIVE

Adults operated for tetralogy of Fallot (TOF) have high risk of ventricular arrhythmias (VA). QRS duration >180 ms is an established risk factor for VA. We aimed to investigate heart function, prevalence of arrhythmias and sex differences in patients with TOF at long-term follow-up.

METHODS

We included TOF-operated patients≥18 years from our centre's registry. We reviewed medical records and the most recent echocardiographic exam. VA was recorded on ECGs, 24-hour Holter registrations and from implantable cardioverter defibrillator.

RESULTS

We included 148 patients (age 37±10 years). Left ventricular global longitudinal strain (LV GLS, -15.8±3.1% vs -18.8±3.2%, p=0.001) and right ventricular (RV) GLS (-15.8±3.9% vs -19.1±4.1%, p=0.001) were lower in men at all ages compared with women. Higher RV D1 (4.3±0.5 cm vs 4.6±0.6 cm, p=0.01), lower ejection fraction (55%±8% vs 50%±9%, p=0.02), lower RV GLS (-18.1±4.0 ms vs -16.1±4.8 ms, p=0.04) and N-terminal pro-brain natriuretic peptide (NT-proBNP) over reference range (n=27 (23%) vs n=8 (77%), p<0.001) were associated with higher incidence of VA. QRS duration was longer in men (151±30 ms vs 128±25 ms, p<0.001). No patients had QRS duration >180 ms. QRS duration did not differ in those with and without VA (143±32 ms vs 137±28 ms, p=0.06).

CONCLUSIONS

Our results confirmed reduced RV function in adults operated for TOF. Male patients had impaired LV and RV function expressed by lower LV and RV GLS values at all ages. Reduced cardiac function and elevated NT-proBNP were associated with higher incidence of VA and may be important in risk assessment.

Macula Densa NOS1β Modulates Renal Hemodynamics and Blood Pressure during Pregnancy: Role in Gestational Hypertension

BACKGROUND

Regulation of renal hemodynamics and BP via tubuloglomerular feedback (TGF) may be an important adaptive mechanism during pregnancy. Because the β-splice variant of nitric oxide synthase 1 (NOS1β) in the macula densa is a primary modulator of TGF, we evaluated its role in normal pregnancy and gestational hypertension in a mouse model. We hypothesized that pregnancy upregulates NOS1β in the macula densa, thus blunting TGF, allowing the GFR to increase and BP to decrease.

METHODS

We used sophisticated techniques, including microperfusion of juxtaglomerular apparatus in vitro, micropuncture of renal tubules in vivo, clearance kinetics of plasma FITC-sinistrin, and radiotelemetry BP monitoring, to determine the effects of normal pregnancy or reduced uterine perfusion pressure (RUPP) on macula densa NOS1β/NO levels, TGF responsiveness, GFR, and BP in wild-type and macula densa-specific NOS1 knockout (MD-NOS1KO) mice.

RESULTS

Macula densa NOS1β was upregulated during pregnancy, resulting in blunted TGF, increased GFR, and decreased BP. These pregnancy-induced changes in TGF and GFR were largely diminished, with a significant rise in BP, in MD-NOS1KO mice. In addition, RUPP resulted in a downregulation in macula densa NOS1β, enhanced TGF, decreased GFR, and hypertension. The superimposition of RUPP into MD-NOS1KO mice only caused a modest further alteration in TGF and its associated changes in GFR and BP. Finally, in African green monkeys, renal cortical NOS1β expression increased in normotensive pregnancies, but decreased in spontaneous gestational hypertensive pregnancies.

CONCLUSIONS

Macula densa NOS1β plays a critical role in the control of renal hemodynamics and BP during pregnancy.

Echocardiographic Assessments for Peripartum Cardiac Events in Pregnant Women with Low-Risk Congenital Heart Disease

This retrospective cohort study aimed to explore the relationship between temporal changes in the cardiac function and peripartum cardiac events in pregnant women with low-risk congenital heart disease.We performed echocardiography at early and late pregnancy and postpartum in 76 pregnant women with low-risk congenital heart disease, and compared echocardiographic parameters between subjects with and without peripartum cardiac events. Median age at delivery was 27 (range, 24-31) years. The ZAHARA and CARPREG II scores suggested that most women were found to be at low-risk for pregnancy. Fifteen subjects had cardiac events that included heart failure in 10, arrhythmia in 4, and pulmonary hypertension in one subject. The left ventricular and atrial volumes significantly increased from early pregnancy toward late pregnancy, and the E/A ratio and global longitudinal strain significantly decreased from early pregnancy toward late pregnancy. The left atrial volume (67 [53-79] versus 45 [35-55] mL, P = 0.002) and plasma brain natriuretic peptide level (58 [36-123] versus 34 [18-48] pg/mL, P = 0.026) at late pregnancy were significantly higher in subjects with cardiac events than in those without cardiac events.An increase in the left atrial volume followed by mild left ventricular diastolic dysfunction is related to peripartum cardiac events in women with congenital heart disease who are at low risk for cardiac events during pregnancy.

Maternal and neonatal outcomes in extra hepatic portal vein obstruction: Our experience

Background:

Women with Extra hepatic portal vein obstruction (EHPVO) are mostly young and belong to Asian countries. In the Indian subcontinent, 20–30% variceal bleeds are caused by EHPVO. Hence pregnancy is a concern in such patients. The objective of this study is to observe the maternal and neonatal outcomes in women with EHPVO.

Materials and Method:

Extra hepatic portal vein obstruction was studied retrospectively in 28 pregnancies in 20 women from Jan 2011 to July 2018 at a tertiary hospital in South India and the pregnancy outcomes were observed during this period. Institutional Review Board approval obtained.

Results:

The mean age of the women was 24.3 years and the mean age of diagnosis was 18.5 years. Splenomegaly, thrombocytopenia and anaemia were seen in 22 (78.5%), 17 (60.7%) and 8 (28.5%) of pregnancies, respectively. Rate of abortions and preterm deliveries were 2 (7.1%, n =28) and 10 (35.7%, n =28). There was one stillbirth (3.6%) in the study group. EHPVO was diagnosed in 25 (89.3%) women prenatally in our series. During pregnancy only one woman had variceal bleed, which was managed conservatively. Blood and blood product transfusion was required in 7(25%) of women and there was no maternal mortality.

Conclusion:

Pregnancies in EHPVO have good maternal and neonatal outcomes, provided they are taken care of by a multidisciplinary approach in a tertiary care centre.

Cardiovascular Imaging and Pregnancy

Cardiovascular disease (CVD) has become increasingly prevalent in women of childbearing age in the western world. This has led to CVD now being the leading cause of maternal morbidity and mortality. In the modern era optimal cardiology care is dependent on cardiovascular imaging and this is especially so in the appropriate management of the pregnant woman with CVD. CVD imaging allows for accurate risk assessment before pregnancy and guides appropriate management during pregnancy. In this article we outline the hemodynamic and structural changes that occur in the cardiovascular system in pregnancy. We examine the role of echocardiography, cardiac magnetic resonance imaging, computed tomography, and coronary angiography within the care of the pregnant patient and highlight the strengths and weaknesses of each.

A Review on the Vagus Nerve and Autonomic Nervous System During Fetal Development: Searching for Critical Windows

The autonomic nervous system (ANS) is one of the main biological systems that regulates the body's physiology. Autonomic nervous system regulatory capacity begins before birth as the sympathetic and parasympathetic activity contributes significantly to the fetus' development. In particular, several studies have shown how vagus nerve is involved in many vital processes during fetal, perinatal, and postnatal life: from the regulation of inflammation through the anti-inflammatory cholinergic pathway, which may affect the functioning of each organ, to the production of hormones involved in bioenergetic metabolism. In addition, the vagus nerve has been recognized as the primary afferent pathway capable of transmitting information to the brain from every organ of the body. Therefore, this hypothesis paper aims to review the development of ANS during fetal and perinatal life, focusing particularly on the vagus nerve, to identify possible "critical windows" that could impact its maturation. These "critical windows" could help clinicians know when to monitor fetuses to effectively assess the developmental status of both ANS and specifically the vagus nerve. In addition, this paper will focus on which factors-i.e., fetal characteristics and behaviors, maternal lifestyle and pathologies, placental health and dysfunction, labor, incubator conditions, and drug exposure-may have an impact on the development of the vagus during the above-mentioned "critical window" and how. This analysis could help clinicians and stakeholders define precise guidelines for improving the management of fetuses and newborns, particularly to reduce the potential adverse environmental impacts on ANS development that may lead to persistent long-term consequences. Since the development of ANS and the vagus influence have been shown to be reflected in cardiac variability, this paper will rely in particular on studies using fetal heart rate variability (fHRV) to monitor the continued growth and health of both animal and human fetuses. In fact, fHRV is a non-invasive marker whose changes have been associated with ANS development, vagal modulation, systemic and neurological inflammatory reactions, and even fetal distress during labor.

A Detailed Review of Critical Care Considerations for the Pregnant Cardiac Patient

Maternal cardiovascular disease is a leading cause of maternal death worldwide and recently, maternal mortality has increased secondary to cardiovascular causes. Maternal admissions to critical care encompass 1%-2% of all critical care admissions, and although not common, the management of the critically ill pregnant patient is complex. Caring for the critically ill pregnant cardiac patient requires integration of pregnancy-associated physiologic changes, understanding pathophysiologic disease states unique to pregnancy, and a multidisciplinary approach to timing around delivery as well as antenatal and postpartum care. Herein we describe cardiorespiratory changes that occur during pregnancy and the differential diagnosis for cardiorespiratory failure in pregnancy. Cardiorespiratory diseases that are either associated or exacerbated by pregnancy are highlighted with emphasis on perturbations secondary to pregnancy and appropriate management strategies. Finally, we describe general management of the pregnant cardiac patient admitted to critical care.

Associations of dietary glycemic index and load during pregnancy with blood pressure, placental hemodynamic parameters and the risk of gestational hypertensive disorders

Purpose

The aim of this study was to examine the associations of dietary glycemic index and load with gestational blood pressure, placental hemodynamic parameters and the risk of gestational hypertensive disorders.

Methods

In a population-based cohort among 3378 pregnant Dutch women, dietary glycemic index and load were assessed from food frequency questionnaires at median 13.4 (95% range 9.9–22.9) weeks gestation. Blood pressure was measured in early-, mid- and late-pregnancy. Placental hemodynamic parameters were measured in mid- and late-pregnancy by ultrasound. Data on gestational hypertensive disorders was acquired from medical records.

Results

Mean dietary glycemic index (SD) was 58 (3) and mean dietary glycemic load (SD) was 155 (47). Dietary glycemic index was not associated with blood pressure, placental hemodynamic parameters and the risk of gestational hypertensive disorders. Higher dietary glycemic load SDS was associated with a higher diastolic blood pressure in early-pregnancy, remaining after adjustment for socio-demographic and lifestyle factors ((0.98 (95% CI 0.35–1.61) mmHg per SDS increase in glycemic load). No other associations of glycemic load with blood pressure or placental hemodynamic parameters and the risk of gestational hypertensive disorders were present. No significant associations of dietary glycemic index and load quartiles with longitudinal blood pressure patterns from early to late-pregnancy were present.

Conclusion

Within this low-risk pregnant population, we did not find consistent associations of dietary glycemic index and load with blood pressure, placental hemodynamic parameters and the risk of gestational hypertensive disorders. Further studies need to assess whether the effects on gestational hemodynamic adaptations are more pronounced among high-risk women with an impaired glucose metabolism.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00394-021-02670-5.

The Nine Month Stress Test: Pregnancy and Exercise - Similarities and Interactions

Of all physiological systems, the cardiovascular system takes on the most profound adaptation in pregnancy to support fetal growth and development. The adaptations that arise are systemic and involve structural and functional changes that can be observed at the cerebral, central, peripheral, and microvascular beds. This includes, although is not limited to increased heart rate, stroke volume and cardiac output with negligible change to blood pressure, reductions in vascular resistance and cerebral blood flow velocity, systemic artery enlargement, enhanced endothelial function. All of this takes place to accommodate blood volume expansion and ensure adequate fetal and maternal oxygen delivery. In some instances, the demand placed on the vasculature can manifest as cardiovascular maladaptation and thus, cardiovascular complications can arise. Exercise is recommended in pregnancy because of its powerful ability to reduce the incidence and severity of cardiovascular complications in pregnancy. However, the mechanism by which it acts is poorly understood. The first aim of this review is to describe the systemic adaptations that take place in pregnancy. Secondly, this review aims to describe the influence of exercise on these systemic adaptations. It is anticipated that this review can comprehensively capture the extent of knowledge in this area while identifying areas that warrant further investigation.

Coronary Events in the Pregnant Patient: Who Is at Risk and How Best to Manage?

Coronary events in pregnancy are a rare but growing cause of maternal morbidity and mortality. Pregnancy presents unique challenges across a broad spectrum of disciplines and requires a multidisciplinary approach to optimise maternal and fetal outcomes. The early involvement of the "cardio-obstetrics" team in prepregnancy counselling, the antenatal period, delivery, and postpartum is vital to ensuring better outcomes for patients at high risk of coronary pathology. The overall risk for coronary events complicating pregnancy is increasing owing to a number of factors, including advancing maternal age and increases in traditional cardiac risk factors contributing to higher rates of maternal morbidity and mortality. The majority of pregnant women experiencing a coronary event do not have previous coronary disease, and the pathologic mechanisms involved are predominantly nonatherosclerotic. Diagnosis and management should follow standard guideline-based practices for acute coronary syndrome (ACS), including the use of diagnostic coronary angiography to guide percutaneous intervention when needed. Management of ACS should not be delayed to facilitate delivery, which can proceed following stent implantation and dual antiplatelet therapy. The timing and mode of delivery should be based on assessment of maternal and fetal status, but vaginal delivery is preferred when possible. This review aims to provide an overview of the major etiologies, risk factors, diagnoses, and management strategies for patients at risk of or presenting with coronary events in pregnancy.

Noninvasively measured radial pressure wave analysis provides insight into cardiovascular changes during pregnancy and menopause

OBJECTIVE

Pregnancy and menopause are significant life events associated with major changes in female hormone levels and changes in cardiovascular health. The role of estrogen in influencing cardiovascular risk is an ongoing research topic. Many studies have provided evidence that radial pressure wave characteristics are an important indicator to consistently and independently predict cardiovascular events. The aim of this study was to investigate if radial pressure wave analysis provided statistical insights into the physiological variations due to pregnancy and menopause. Furthermore, the study investigated how these variations could serve as an indicator for cardiovascular risks. As the radial pulse measurement is non-invasive and speedy, it may be helpful in evaluating cardiovascular changes and risk during these transitions.

MATERIALS AND METHOD

A total of 702 randomly selected female subjects (90 pregnant and 97 post-menopausal), aged 20-59, enrolled in the study. The visit measured the subject's hemodynamic parameters including heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP) and radial pressure waves. SBP and DBP were evaluated by an automatic blood pressure monitor. Radial pressure wave data were continuously recorded for 12-s using a TD01C pulse measuring instrument. Spectrum analysis of the radial pressure wave was performed to evaluate the first five harmonic components (C1-C5).

RESULTS

A comparison of pregnant women to non-pregnant women showed C3 and C5 were lower. Heart rate C2 and C4 were higher in pregnant women. A comparison of women pre-menopausal and post-menopausal showed no significant difference in SBP or DBP. Menopause significantly changed the C1 and C4 radial pressure wave harmonics. An increase in C1 and a decrease in C4 were observed.

CONCLUSION AND DISCUSSION

This study provided further clinical evidence to support the hemodynamic model that describes the cardiovascular changes and risks related to the harmonic components of the pulse spectrum. Beyond blood pressure, the effects of menopause on the radial pressure wave, especially on hemodynamic index C4, independent of age and BMI, may explain increased post-menopausal cardiovascular risk. This and past studies collectively suggest that radial pressure wave components may be an indicator of a female body's ability to supply oxygen and nutrients. Harmonic analysis of the radial pressure wave may provide additional insights into the underlying mechanism of the cardiovascular changes over the lifespan of a woman.

Cord Serum Calcitriol Inversely Correlates with Maternal Blood Pressure in Urinary Tract Infection-Affected Pregnancies: Sex-Dependent Immune Implications

Urinary tract infections (UTI) during pregnancy are frequently associated with hypertensive disorders, increasing the risk of perinatal morbidity. Calcitriol, vitamin D3's most active metabolite, has been involved in blood pressure regulation and prevention of UTIs, partially through modulating vasoactive peptides and antimicrobial peptides, like cathelicidin. However, nothing is known regarding the interplay between placental calcitriol, cathelicidin, and maternal blood pressure in UTI-complicated pregnancies. Here, we analyzed the correlation between these parameters in pregnant women with UTI and with normal pregnancy (NP). Umbilical venous serum calcitriol and its precursor calcidiol were significantly elevated in UTI. Regardless of newborn's sex, we found strong negative correlations between calcitriol and maternal systolic and diastolic blood pressure in the UTI cohort (p < 0.002). In NP, this relationship was observed only in female-carrying mothers. UTI-female placentas showed higher expression of cathelicidin and CYP27B1, the calcitriol activating-enzyme, compared to male and NP samples. Accordingly, cord-serum calcitriol from UTI-female neonates negatively correlated with maternal bacteriuria. Cathelicidin gene expression positively correlated with gestational age in UTI and with newborn anthropometric parameters. Our results suggest that vitamin D deficiency might predispose to maternal cardiovascular risk and perinatal infections especially in male-carrying pregnancies, probably due to lower placental CYP27B1 and cathelicidin expression.

The Canadian Women’s Heart Health Alliance Atlas on the Epidemiology, Diagnosis, and Management of Cardiovascular Disease in Women — Chapter 4: Sex- and Gender-Unique Disparities: CVD Across the Lifespan of a Woman

Women have unique sex- and gender-related risk factors for cardiovascular disease (CVD) that can present or evolve over their lifespan. Pregnancy-associated conditions, polycystic ovarian syndrome, and menopause can increase a woman’s risk of CVD. Women are at greater risk for autoimmune rheumatic disorders, which play a role in the predisposition and pathogenesis of CVD. The influence of traditional CVD risk factors (eg, smoking, hypertension, diabetes, obesity, physical inactivity, depression, anxiety, and family history) is greater in women than men. Finally, there are sex differences in the response to treatments for CVD risk and comorbid disease processes. In this Atlas chapter we review sex- and gender-unique CVD risk factors that can occur across a woman’s lifespan, with the aim to reduce knowledge gaps and guide the development of optimal strategies for awareness and treatment.

Mitral Regurgitation in Patients Undergoing Noncardiac Surgery

Mitral regurgitation (MR) is one of the most frequently encountered types of valvular heart disease in the United States. Patients with significant MR (moderate-to-severe or severe) undergoing noncardiac surgery have an increased risk of perioperative cardiovascular complications. MR can arise from a diverse array of causes that fall into 2 broad categories: primary (diseases intrinsic to the valvular apparatus) and secondary (diseases that disrupt normal valve function via effects on the left ventricle or mitral annulus). This article highlights key guideline updates from the American College of Cardiologists (ACC) and the American Heart Association (AHA) that inform decision-making for the anesthesiologist caring for a patient with MR undergoing noncardiac surgery. The pathophysiology and natural history of acute and chronic MR, staging of chronic primary and secondary MR, and considerations for timing of valvular corrective surgery are reviewed. These topics are then applied to a discussion of anesthetic management, including preoperative risk evaluation, anesthetic selection, hemodynamic goals, and intraoperative monitoring of the noncardiac surgical patient with MR.

The Pattern of Valvular Heart Diseases in India During Pregnancy and Its Outcomes

INTRODUCTION

The incidence of rheumatic heart disease is very high in India. The data on the pattern of valvular heart diseases during pregnancy and its outcomes is very scarce. Again, the data in the Indian scenario, the differences in outcomes between different grades of valvular heart diseases and its impact on pregnancy outcomes is very less. We planned to study the different patterns of valvular heart diseases during pregnancy and their outcomes with respect to cardiac complication and perinatal outcomes.

MATERIALS AND METHODS

It was a hospital-based prospective observational study. We recruited 71 patients after taking written informed consent. All patients were with term gestation and valvular heart diseases. We did 2D echocardiography to analyze the valve lesion and assess the valve lesion with its maternal and perinatal outcomes.

RESULTS

The mean age of participants in the study was 27 + 5.2 years. A total of 54 patients (76.1%) were less than 30 years and 17 (23.9%) were more than 30 years of age. Six patients (8.5%) presented with New York Heart Association (NYHA) class I, 39 patients (54.9%) presented with NYHA class II, 25 patients (35.2%) presented with NYHA class III and one patient (1.4%) presented with NYHA class IV. The most common etiology of valvular heart diseases was found to be rheumatic in 62 patients (87.3%). The most common valve involved was the mitral valve (69%). New-onset atrial fibrillation (AF) was reported in 26.8% patients and pulmonary edema developed in 15.5% patients. Live birth was observed in 66 patients (93%) compared to stillbirth reported in five patients (7%).

CONCLUSION

No significant difference in maternal and perinatal outcomes between moderate and severe grades of different valvular heart diseases.

Circulating Maternal sFLT1 (Soluble fms-Like Tyrosine Kinase-1) Is Sufficient to Impair Spiral Arterial Remodeling in a Preeclampsia Mouse Model

Supplemental Digital Content is available in the text.

One driving factor for developing preeclampsia—a pregnancy disorder, often associated with poor spiral artery (SpA)-remodeling and fetal growth restriction—is the anti-angiogenic sFLT1 (soluble fms-like tyrosine kinase-1), which is found to be highly upregulated in preeclampsia patients. The sFLT1-mediated endothelial dysfunction is a common theory for the manifestation of maternal preeclampsia symptoms. However, the influence of sFLT1 on SpA-remodeling and the link between placental and maternal preeclampsia symptoms is less understood. To dissect the hsFLT1 (human sFLT1) effects on maternal and/or fetoplacental physiology in preeclampsia, sFLT1-transgenic mice with systemic hsFLT1 overexpression from midgestation onwards were used. SpA-remodeling was analyzed on histological and molecular level in placental/mesometrial triangle tissues. Maternal kidney and aorta morphology was investigated, combined with blood pressure measurements via telemetry. hsFLT1 overexpression resulted in maternal hypertension, aortic wall thickening, and elastin breakdown. Furthermore, maternal kidneys showed glomerular endotheliosis, podocyte damage, and proteinuria. preeclampsia symptoms were combined with fetal growth restriction already at the end of the second trimester and SpA-remodeling was strongly impaired as shown by persisted vascular smooth muscle cells. This phenotype was associated with shallow trophoblast invasion, delayed presence of uterine natural killer cells, and altered lymphatic angiogenesis. Overall, this study showed that circulating maternal hsFLT1 is sufficient to induce typical maternal preeclampsia-like symptoms in mice and impair the SpA-remodeling independent from the fetoplacental compartment, revealing new insights into the interaction between the placental and maternal contribution of preeclampsia.

Role of ACE2 in pregnancy and potential implications for COVID-19 susceptibility

In times of coronavirus disease 2019 (COVID-19), the impact of severe acute respiratory syndrome (SARS)-coronavirus (CoV)-2 infection on pregnancy is still unclear. The presence of angiotensin-converting enzyme (ACE) 2 (ACE2), the main receptor for SARS-CoV-2, in human placentas indicates that this organ can be vulnerable for viral infection during pregnancy. However, for this to happen, additional molecular processes are critical to allow viral entry in cells, its replication and disease manifestation, particularly in the placenta and/or feto-maternal circulation. Beyond the risk of vertical transmission, COVID-19 is also proposed to deplete ACE2 protein and its biological actions in the placenta. It is postulated that such effects may impair essential processes during placentation and maternal hemodynamic adaptations in COVID-19 pregnancy, features also observed in several disorders of pregnancy. This review gathers information indicating risks and protective features related to ACE2 changes in COVID-19 pregnancies. First, we describe the mechanisms of SARS-CoV-2 infection having ACE2 as a main entry door and current evidence of viral infection in the placenta. Further, we discuss the central role of ACE2 in physiological systems such as the renin-angiotensin system (RAS) and the kallikrein-kinin system (KKS), both active during placentation and hemodynamic adaptations of pregnancy. Significant knowledge gaps are also identified and should be urgently filled to better understand the fate of ACE2 in COVID-19 pregnancies and the potential associated risks. Emerging knowledge will be able to improve the early stratification of high-risk pregnancies with COVID-19 exposure as well as to guide better management and follow-up of these mothers and their children.

Uteroplacental Circulation in Normal Pregnancy and Preeclampsia: Functional Adaptation and Maladaptation

Uteroplacental blood flow increases as pregnancy advances. Adequate supply of nutrients and oxygen carried by uteroplacental blood flow is essential for the well-being of the mother and growth/development of the fetus. The uteroplacental hemodynamic change is accomplished primarily through uterine vascular adaptation, involving hormonal regulation of myogenic tone, vasoreactivity, release of vasoactive factors and others, in addition to the remodeling of spiral arteries. In preeclampsia, hormonal and angiogenic imbalance, proinflammatory cytokines and autoantibodies cause dysfunction of both endothelium and vascular smooth muscle cells of the uteroplacental vasculature. Consequently, the vascular dysfunction leads to increased vascular resistance and reduced blood flow in the uteroplacental circulation. In this article, the (mal)adaptation of uteroplacental vascular function in normal pregnancy and preeclampsia and underlying mechanisms are reviewed.

Arrhythmias and Pregnancy: Management of Preexisting and New-Onset Maternal Arrhythmias

Arrhythmias are the most common cardiovascular complication of pregnancy in women with and without structural heart disease. Appropriate maternal diagnosis and management is of utmost importance to optimize maternal and fetal outcomes. A multidisciplinary care approach with cardiology, maternal fetal medicine, anesthesia, and pediatrics is important for preconceptional, pregnancy, and delivery planning.

The Importance of Cardiovascular Risk Assessment and Pregnancy Heart Team in the Management of Cardiovascular Disease in Pregnancy

Pregnancy-related maternal morbidity and mortality is increasing because of complications from cardiovascular disease. Pregnancy results in physiologic changes that can adversely impact the cardiovascular system and lead to adverse pregnancy outcomes. A multidisciplinary pregnancy heart team is essential to safely navigate women with heart disease through pregnancy. This role of the pregnancy heart team is to offer preconception counseling, determine pregnancy risks and educate women about those risks, develop a comprehensive antenatal and delivery plan, and ensure appropriate postpartum follow-up. These steps are important to improve cardiovascular outcomes in pregnancy.

Associations Between Trajectory of Different Blood Pressure Components in Pregnancy and Risk of Adverse Birth Outcomes - A Real World Study

Background

High blood pressure during pregnancy has been suggested to be associated with adverse birth outcomes (ABO), but it is unclear how different blood pressure changes and the extent of the effect. Therefore, we aimed to investigate the association between blood pressure trajectories (systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), pulse pressure (PP)) of pregnant women and ABO in a real-world study.

Material and Methods

Leveraging 28,679 pregnant women and their fetuses from a register-based cohort from January 1, 2010, to December 31, 2019. Blood pressure trajectories were estimated by package “traj” in R software using real-world blood pressure data of routine antenatal care examinations. Logistic regression models were applied to examine the association between trajectories of different blood pressure components (SBP, DBP, MAP, and PP) during pregnancy and the risk of ABO.

Results

Trajectories of all blood pressure components were identically labeled as low-stable, moderate-increasing, moderate-decreasing and high-stable. After adjusting for confounding factors, compared with pregnant women with the low-stable pattern, pregnant women with a high-stable or moderate-increasing pattern had a significantly increased risk of developing adverse birth outcomes. Pregnant women with a moderate-decreasing pattern had no significant increased risk of ABO but had a lower risk of adverse birth outcomes than those with a moderate-increasing pattern. The trajectories crossed at 17–20 weeks of gestation for all blood pressure components.

Conclusion

Our study results indicated that reduction and maintenance of blood pressure to a low level of less than 110 mmHg for SBP and 65 mmHg for DBP after 20 weeks of gestation would benefit prevention of adverse birth outcomes, regardless of the level of blood pressure at early pregnancy.

Exposure to heavy metals and trace minerals in first trimester and maternal blood pressure change over gestation

BACKGROUND

While several heavy metals and trace minerals have been linked with hypertensive disorders during pregnancy (HDP) in women, no studies have estimated the relationship of exposure to these chemicals, both independently and as a mixture, with systolic blood pressure (SBP) or diastolic blood pressure (DBP) over gestation.

OBJECTIVES

We examined individual and joint effects of 1^st trimester chemicals with SBP and DBP over gestation, and whether those chemicals were associated with HDP.

METHODS

We used data from 1832 non-obese pregnant women with low-risk antenatal profiles from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies - Singleton cohort (2009-2013). In plasma collected from women at 8-13 weeks' gestation (baseline enrollment), we measured heavy metals, barium (Ba), cesium (Cs), antimony (Sb), as well as trace minerals, cobalt (Co), copper (Cu), molybdenum (Mo), selenium (Se), and zinc (Zn). We obtained BP at baseline and throughout gestation until delivery and diagnosis of HDP from medical records. We used Bayesian Kernel Machine Regression (BKMR) as well as traditional linear and logistic regressions to examine the cross-sectional associations of chemicals with baseline BP and HDP. We used linear mixed effect regression to examine longitudinal associations between chemicals and rate of weekly change in BP in each trimester. We adjusted for sociodemographic and lifestyle factors and pre-pregnancy body mass index in all models.

RESULTS

BKMR revealed that comparing the entire chemical mixture at the 90^th percentile vs. the 50^th percentile was associated with a 1.61 mmHg (95% CI: 0.41, 2.81) higher SBP and a 1.09 mmHg (0.10, 2.09) higher DBP. No interactions were observed between chemicals. Accounting for chemical co-exposure in BKMR, each interquartile range (IQR) increment in Cu was associated with a 0.67 mmHg (0.02, 1.32) higher SBP and a 0.60 mmHg (0.08, 1.12) higher DBP at baseline; each IQR increment in Se was associated with a 0.67 mmHg (0.05, 1.29) higher SBP but not DBP. In longitudinal analyses, women with higher (i.e., above median concentration) baseline Cu had a 0.09 mmHg (0.01, 0.17) and 0.06 mmHg (0.001, 0.12) larger weekly decrease in SBP and DBP in 2^nd trimester, respectively. Women with higher baseline Ba had a 0.12 mmHg (0.04, 0.20) larger weekly increase in SBP in 2^nd trimester, while women with higher Cs had a 0.05 mmHg (0.01, 0.10) larger weekly increase in DBP in 3^rd trimester. None of the chemicals examined were significantly associated with HDP.

CONCLUSIONS

In this multi-ethnic cohort of women with low antenatal risk, plasma metals and trace minerals in early pregnancy, both individually and as a mixture, were statistically significantly associated with BP during gestation in small magnitude and in different directions, but not with HDP. The implications of these findings for women's postpartum BP and future cardiovascular health remains to be investigated.

Effect of maternal age on cardiac adaptation in pregnancy

OBJECTIVE

To compare longitudinal maternal hemodynamic changes throughout gestation between different age groups.

METHODS

This was a prospective longitudinal study assessing maternal hemodynamics using a bioreactance technique at 11 + 0 to 13 + 6, 19 + 0 to 24 + 0, 30 + 0 to 34 + 0 and 35 + 0 to 37 + 0 weeks' gestation. Women were divided into four groups according to maternal age at the first visit at 11 + 0 to 13 + 6 weeks: Group 1, < 25.0 years; Group 2, 25.0-30.0 years; Group 3, 30.1-34.9 years; and Group 4, ≥ 35.0 years. A multilevel linear mixed-effects model was performed to compare the repeat measurements of hemodynamic variables, correcting for demographics, medical and obstetric history, pregnancy complications, maternal age and gestational-age window.

RESULTS

The study population included 254 women in Group 1, 442 in Group 2, 618 in Group 3 and 475 in Group 4. Younger women (Group 1) had the highest cardiac output (CO) and lowest peripheral vascular resistance (PVR), and older women (Group 4) had the lowest CO and highest PVR throughout pregnancy. The higher CO seen in younger women was achieved through an increase in heart rate alone and not with a concomitant rise in stroke volume. Although the youngest age group demonstrated an apparently more favorable hemodynamic profile, it had the highest incidence of a small-for-gestational-age neonate. There was no significant difference between the groups in the incidence of pre-eclampsia.

CONCLUSION

Age-specific differences in maternal hemodynamic adaptation do not explain the differences in the incidence of a small-for-gestational-age neonate between age groups. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

A case of mistaken arrhythmogenic identity during pregnancy

Atypical LVOT ectopy can present with an RVOT morphology on ECG and differentiation to reveal this focus is in favor of benign idiopathic ventricular ectopy over an arrhythmogenic cardiomyopathy.

The effect of bearing and rearing a child on blood pressure: a nationally representative instrumental variable analysis of 444611 mothers in India

BACKGROUND

At the individual level, it is well known that pregnancies have a short-term effect on a woman's cardiovascular system and blood pressure. The long-term effect of having children on maternal blood pressure, however, is unknown. We thus estimated the causal effect of having children on blood pressure among mothers in India, a country with a history of high fertility rates.

METHODS

We used nationally representative cross-sectional data from the 2015-16 India National Family and Health Survey (NFHS-4). The study population comprised 444 611 mothers aged 15-49 years. We used the sex of the first-born child as an instrumental variable (IV) for the total number of a woman's children. We estimated the effect of an additional child on systolic and diastolic blood pressure in IV (two-stage least squares) regressions. In additional analyses, we stratified the IV regressions by time since a mother last gave birth. Furthermore, we repeated our analyses using mothers' husbands and partners as the regression sample.

RESULTS

On average, mothers had 2.7 children [standard deviation (SD): 1.5], a systolic blood pressure of 116.4 mmHg (SD: 14.4) and diastolic blood pressure of 78.5 mmHg (SD: 9.4). One in seven mothers was hypertensive. In conventional ordinary least squares regression, each child was associated with 0.42 mmHg lower systolic [95% confidence interval (CI): -0.46 to -0.39, P < 0.001] and 0.13 mmHg lower diastolic (95% CI: -0.15 to -0.11, P < 0.001) blood pressure. In the IV regressions, each child decreased a mother's systolic blood pressure by an average of 1.00 mmHg (95% CI: -1.26 to -0.74, P < 0.001) and diastolic blood pressure by an average of 0.35 mmHg (95% CI: -0.52 to -0.17, P < 0.001). These decreases were sustained over more than a decade after childbirth, with effect sizes slightly declining as the time since last birth increased. Having children did not influence blood pressure in men.

CONCLUSIONS

Bearing and rearing a child decreases blood pressure among mothers in India.

Management of Ischemic Heart Disease in Pregnancy

PURPOSE OF REVIEW

Cardiovascular disease is an escalating cause of maternal morbidity and mortality. Women are at risk for acute myocardial infarction (MI), and more are living with risk factors for ischemic heart disease (IHD). The purpose of this review is to describe the evaluation and management of women at risk for and diagnosed with IHD in pregnancy.

RECENT FINDINGS

Pregnancy can provoke MI which has been estimated as occurring in 1.5-10/100, 000 deliveries or 1/12,400 hospitalizations, with a high inpatient mortality rate of approximately 5-7%. An invasive strategy may or may not be preferred, but fetal radiation exposure is less of a concern in comparison to maternal mortality. Common medications used to treat IHD may be continued successfully during pregnancy and lactation, including aspirin, which has an emerging role in pregnancy to prevent preeclampsia, preterm labor, and maternal mortality. Hemodynamics can be modulated during pregnancy, labor, and postpartum to mitigate risk for acute decompensation in women with IHD. Cardiologists can successfully manage IHD in pregnancy with obstetric partners and should engage women in a lifetime of cardiovascular care.

Stroke in Pregnancy: A Multidisciplinary Approach

Pregnancy confers a substantially increased risk of stroke, especially during the third trimester and until 6 weeks postpartum. Hypertensive disorders of pregnancy and gestational hypercoagulability are important contributors to obstetric stroke. Preeclampsia and eclampsia confer risk for future cardiovascular disease. Hemorrhagic stroke is the most common type of obstetric stroke. Ischemic stroke can result from cardiomyopathy, paradoxical embolism, posterior reversible encephalopathy, reversible cerebral vasoconstriction syndrome, and dissections. Cerebral venous sinus thrombosis is a frequent complication of pregnancy.

A longitudinal analysis of arterial stiffness and wave reflection in preeclampsia: Identification of changepoints

PURPOSE

Preeclampsia (PrE) is a leading complication of pregnancy characterized by vascular dysfunction. Characterizing the longitudinal changes in vascular function prior to PrE onset is critical to the identification of optimal timepoints for vascular assessment and the development of effective early screening strategies.

METHODS

In this prospective longitudinal study of women with singleton high-risk pregnancies, arterial stiffness and wave reflection parameters were assessed using applanation tonometry at 10-13 weeks' gestation and repeated every 4 weeks throughout pregnancy. Changepoints in carotid-femoral pulse wave velocity (cfPWV), carotid-radial PWV (crPWV), augmentation index (AIx), time to wave reflection (T_1R), pulse pressure amplification (PPA), and subendocardial viability ratio (SEVR) were compared between women who did and did not subsequently develop PrE.

RESULTS

A changepoint in cfPWV and crPWV was detected at 14-17 weeks' gestation. cfPWV then increased in women who went on to develop PrE but decreased in women who did not; a 1.2 m/s difference in cfPWV between the groups was observed at 22-25 weeks' gestation. Conversely, crPWV converged in the two groups from a baseline difference of 1.05 m/s (95% credible interval: 0.37, 1.72). Women who subsequently developed PrE demonstrated an increase in AIx at 18-21 weeks' gestation that was not seen in women who did not develop PrE until 30-33 weeks. No differences in T_1R, PPA, or SEVR were observed between the groups.

CONCLUSIONS

Altered vascular adaptations were detected using measures of arterial stiffness and wave reflection in the early second trimester of pregnant women who developed PrE compared to those who did not. These findings demonstrate the potential clinical utility of arterial stiffness and wave reflection parameters as an early screening tool for PrE, which can be used to inform clinical management of high-risk pregnancies.

Heat loss responses at rest and during exercise in pregnancy: A scoping review

BACKGROUND

The teratogenic risk associated with maternal hyperthermia (i.e., core temperature ≥39.0 °C) has been a crucial motive in understanding thermoregulatory responses in pregnancy. To date, a substantial number of studies have focused on core temperature responses in a wide range of exercise intensities, duration, and ambient temperatures. Fortunately, none have reported core temperatures exceeding 39.0 °C. Nonetheless, there are limited studies that have provided substantial insight into both dry and evaporative heat loss mechanisms involved in facilitating the maintenance of core temperature (≥39.0 °C) during heat stress in pregnant women. The purpose of this scoping review was to summarize the available literature that has assessed heat loss responses in studies of human pregnancy.

METHODS

A search strategy was developed combining the terms pregnancy, thermoregulation, and adaptation. A systematic search was performed in the following databases: PubMed, Embase, Scopus, and ProQuest. Studies eligible for inclusion included pregnant women between the ages of 18-40 years old, and at least one measurement of the following: sweating, blood flow, skin temperature, and behavioural responses. Retrieved data were categorized as evaporative (sweating), dry or behavioural heat loss responses and summarized narratively.

RESULTS

Thirty-three studies were included in this review (twenty-nine measured physiological responses and four measured behavioural responses). Studies suggest that during exercise, evaporative (sweating) and dry (skin blood flow and temperature) heat loss responses increase from early to late pregnancy in addition to greater cardiac output, blood volume and reduced vascular resistance. Behavioural practices related to heat loss responses are also influenced by cultural/religious expectations, personal preferences and sociodemographics.

CONCLUSION

The findings from this review suggest that pregnancy modifies evaporative (sweating), dry and behavioural heat loss. However, future studies have an opportunity to compare heat loss measurements accounting for gestational weight gain and thermal sensation/comfort scale to associate physiological responses with perceptual responses across pregnancy.

Rheumatic heart disease in pregnancy and neonatal outcomes: A systematic review and meta-analysis

Purpose

Associations between rheumatic heart disease (RHD) in pregnancy and fetal outcomes are relatively unknown. This study aimed to review rates and predictors of major adverse fetal outcomes of RHD in pregnancy.

Methods

Medline (Ovid), Pubmed, EMcare, Scopus, CINAHL, Informit, and WHOICTRP databases were searched for studies that reported rates of adverse perinatal events in women with RHD during pregnancy. Outcomes included preterm birth, intra-uterine growth restriction (IUGR), low-birth weight (LBW), perinatal death and percutaneous balloon mitral valvuloplasty intervention. Meta-analysis of fetal events by the New-York Heart Association (NYHA) heart failure classification, and the Mitral-valve Area (MVA) severity score was performed with unadjusted random effects models and heterogeneity of risk ratios (RR) was assessed with the I² statistic. Quality of evidence was evaluated using the GRADE approach. The study was registered in PROSPERO (CRD42020161529).

Findings

The search identified 5949 non-duplicate records of which 136 full-text articles were assessed for eligibility and 22 studies included, 11 studies were eligible for meta-analyses. In 3928 pregnancies, high rates of preterm birth (9.35%-42.97%), LBW (12.98%-39.70%), IUGR (6.76%-22.40%) and perinatal death (0.00%-9.41%) were reported. NYHA III/IV pre-pregnancy was associated with higher rates of preterm birth (5 studies, RR 2.86, 95%CI 1.54–5.33), and perinatal death (6 studies, RR 3.23, 1.92–5.44). Moderate /severe mitral stenosis (MS) was associated with higher rates of preterm birth (3 studies, RR 2.05, 95%CI 1.02–4.11) and IUGR (3 studies, RR 2.46, 95%CI 1.02–5.95).

Interpretation

RHD during pregnancy is associated with adverse fetal outcomes. Maternal NYHA III/IV and moderate/severe MS in particular may predict poor prognosis.

Neurocritical Care of the Pregnant Patient

Purpose of review

To summarize recent changes in management and emerging therapies for pregnant neurocritical care patients.

Recent findings

Diagnostic and treatment options for managing neurologic emergencies in pregnant patients have expanded with both greater understanding of the effects of imaging modalities and medications on pregnancy and application of standard treatments for non-pregnant patients to pregnant populations. Specifically, this includes cerebrovascular diseases (pregnancy-associated ischemic stroke, pregnancy-associated intracerebral hemorrhage, cerebral venous sinus thrombosis), post-maternal cardiac arrest care, seizures and status epilepticus, myasthenia gravis, and fetal somatic support in maternal death by neurologic criteria.

Summary

With the exception of direct abdominal computed tomography (CT), most imaging studies are reasonably safe in pregnancy. When emergent imaging is needed to prevent maternal morbidity or mortality, any CT sequence with or without contrast is appropriate to pursue. Though new safety data on antiplatelets, antihypertensives, thrombolytics, and antiepileptic drugs have increased options for disease management in pregnancy, unfractionated and low-molecular weight heparin remain the safest options for anticoagulation. Early studies on hypothermia, ketamine, and immunomodulating therapies in pregnancy are promising. In myasthenia gravis, new data on adjunct devices may allow more patients to undergo safe vaginal delivery, avoiding cesarean section and the associated risk of crisis. When difficult decisions regarding preterm delivery arise, recent outcome studies can help inform discussion. Lastly, when the feared complication of maternal death by neurologic criteria occurs, fetal somatic support may help to save at least one life.

Blood pressure and cardiac output during caesarean delivery under spinal anaesthesia: a prospective cohort study

OBJECTIVES

We have previously established a method to measure transfer of nutrients between mother, placenta and fetus in vivo. The method includes measurements of maternal and fetal blood flow by Doppler ultrasound prior to spinal anaesthesia. Spinal anaesthesia affects maternal blood pressure and cardiac output. We aimed to determine the effect of spinal anaesthesia in mothers undergoing an elective caesarean section on blood pressure, heart rate and cardiac output, and whether cardiac output levels were comparable before induction of spinal anaesthesia and before delivery.

DESIGN

Prospective cohort study.

SETTING

Tertiary hospital in Norway.

PARTICIPANTS

76 healthy women with uneventful pregnancies undergoing an elective caesarean section.

INTERVENTIONS

We induced spinal anaesthesia with a standard prevention of hypotension including intravenous fluid coloading and phenylephrine infusion.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary outcome measure was maternal cardiac output, and secondary outcome measures were invasive systolic blood pressure and heart rate. We measured heart rate and blood pressure by continuous invasive monitoring with a cannula in the radial artery. Cardiac output was estimated based on continuous arterial waveform. We compared maternal parameters 30 s before induction of spinal anaesthesia to 30 s before delivery.

RESULTS

Median age at delivery was 34.5 (range 21-43) years and 17 of 76 women were nulliparous. The most prevalent indications were previous caesarean section and maternal request. Among 76 included women, 71 had sufficient data for analysis of endpoints. Median cardiac output was 6.51 (IQR (5.56-7.54) L/min before spinal anaesthesia and 6.40 (5.83-7.56) L/min before delivery (p=0.40)). Median invasive systolic blood pressure increased from 128.5 (120.1-142.7) mm Hg to 134.1 (124.0-146.6) mm Hg (p=0.014), and mean heart rate decreased from 86.0 (SD 13.9) to 75.2 (14.2) (p<0.001).

CONCLUSIONS

Maternal cardiac output at the time of caesarean delivery is comparable to levels before induction of spinal anaesthesia.

TRIAL REGISTRATION NUMBER

NCT00977769.

Associations of body composition and physical fitness with gestational diabetes and cardiovascular health in pregnancy: Results from the HealthyMoms trial

The aim of this study was to examine associations of body composition (fat mass index, % fat mass, fat-free mass index, body mass index) and physical fitness (cardiorespiratory fitness and handgrip strength) with gestational diabetes and cardiovascular health in early pregnancy. This cross-sectional study utilized baseline data (n = 303) collected in early pregnancy from the HealthyMoms trial. Body composition was measured using air-displacement plethysmography, cardiorespiratory fitness was assessed by means of the 6-min walk test and handgrip strength using a dynamometer. Logistic regression was used to estimate odds ratios (ORs) for gestational diabetes as well as high (defined as 1 SD above the mean) blood pressure, homeostatic model assessment for insulin resistance (HOMA-IR), and metabolic syndrome score (MetS score) per 1 SD increase in body composition and fitness variables. Fat mass index, % fat mass and body mass index were all strongly associated with gestational diabetes (ORs: 1.72–2.14, P ≤ 0.003), HOMA-IR (ORs: 3.01–3.80, P < 0.001), blood pressure (ORs: 1.81–2.05, P < 0.001) and MetS score (ORs: 3.29–3.71, P < 0.001). Associations with fat-free mass index were considerably weaker (ORs: 1.26–1.82, P = 0.001–0.15) and were strongly attenuated after adjustments for fat mass index (ORs: 0.88–1.54, P = 0.039–0.68). Finally, greater cardiorespiratory fitness was associated with lower risk of high HOMA-IR and MetS score (ORs: 0.57–0.63, P  ≤ 0.004) although these associations were attenuated when accounting for fat mass index (ORs: 1.08-1.11, P ≥ 0.61). In conclusion, accurately measured fat mass index or % fat mass were strongly associated with gestational diabetes risk and markers of cardiovascular health although associations were not stronger than the corresponding ones for body mass index. Fat-free mass index had only weak associations with gestational diabetes and cardiovascular health which support that the focus during clinical care would be on excess fat mass and not fat-free mass.

Uterine Vascular Control Preconception and During Pregnancy

Successful pregnancy and reproduction are dependent on adequate uterine blood flow, placental perfusion, and vascular responsivity to fetal demands. The ability to support pregnancy centers on systemic adaptation and endometrial preparation through decidualization, embryonic implantation, trophoblast invasion, arterial/arteriolar reactivity, and vascular remodeling. These adaptations occur through responsiveness to endocrine signaling and local uteroplacental mediators. The purpose of this article is to highlight the current knowledge associated with vascular remodeling and responsivity during uterine preparation for and during pregnancy. We focus on maternal cardiovascular systemic and uterine modifications, endometrial decidualization, implantation and invasion, uterine and spiral artery remodeling, local uterine regulatory mechanisms, placentation, and pathological consequences of vascular dysfunction during pregnancy. © 2021 American Physiological Society. Compr Physiol 11:1-23, 2021.

Prenatal Exercise and Cardiovascular Health (PEACH) Study: Impact on Muscle Sympathetic Nerve (Re)Activity

PURPOSE

Women who develop gestational hypertension have evidence of elevated muscle sympathetic nerve activity (MSNA) in early pregnancy, which continues to rise after diagnosis. Exercise has been shown to play a preventative role in the development of gestational hypertension and has been shown to reduce resting and reflex MSNA in nonpregnant populations. We sought to investigate whether aerobic exercise affected the sympathetic regulation of blood pressure between the second and third trimesters of pregnancy.

METHODS

We conducted a randomized controlled trial of structured aerobic exercise (n = 31) compared with no intervention (control, n = 28) beginning at 16-20 wk and continuing until 34-36 wk of gestation (NCT02948439). Women in the exercise group were prescribed aerobic activity at 50%-70% of their heart rate reserve, on 3-4 d·wk-1 for 25-40 min with a 5-min warm-up and 5-min cool-down (i.e., up to 160 min total activity per week). At preintervention and postintervention assessments, data from ~10 min of quiet rest and a 3-min cold pressor test were analyzed to determine sympathetic nervous system activity and reactivity.

RESULTS

MSNA was obtained in 51% of assessments. Resting MSNA burst frequency and burst incidence increased across gestation (main effect of gestational age, P = 0.002). Neurovascular transduction was blunted in the control group (P = 0.024) but not in exercisers (P = 0.873) at the postintervention time point. Lastly, MSNA reactivity during the cold pressor test was not affected by gestational age or exercise (P = 0.790, interaction).

CONCLUSIONS

These data show that exercise attenuates both the rise in MSNA and the blunting of neurovascular transduction. This may partially explain the lower risk of developing gestational hypertension in women who are active during their pregnancies.

Prevention of Pathological Atrial Remodeling and Atrial Fibrillation: JACC State-of-the-Art Review

Atrial enlargement in response to pathological stimuli (e.g., hypertension, mitral valve disease) and physiological stimuli (exercise, pregnancy) can be comparable in magnitude, but the diseased enlarged atria is associated with complications such as atrial fibrillation (AF), whereas physiological atrial enlargement is not. Pathological atrial enlargement and AF is also observed in a small percentage of athletes undergoing extreme/intense endurance sport and pregnant women with preeclampsia. Differences between physiological and pathological atrial enlargement and underlying mechanisms are poorly understood. This review describes human and animal studies characterizing atrial enlargement under physiological and pathological conditions and highlights key knowledge gaps and clinical challenges, including: 1) the limited ability of atria to reverse remodel; and 2) distinguishing physiological and pathological enlargement via imaging/biomarkers. Finally, this review discusses how targeting distinct molecular mechanisms underlying physiological and pathological atrial enlargement could provide new therapeutic and diagnostic strategies for preventing or reversing atrial enlargement and AF.

Influences of adversity across the lifespan on respiratory sinus arrhythmia during pregnancy

There is limited understanding of factors across the lifespan that influence pregnant women's respiratory sinus arrhythmia (RSA), which could have implications for their health and offspring development. We examined associations among 162 English- and Spanish-speaking pregnant women's childhood maltreatment history, emotion dysregulation, recent life stress, and resting RSA during the third trimester. Moderated mediation analyses indicated that more severe childhood maltreatment history (95% confidence interval (CI) [0.26, 0.63]) and higher emotion dysregulation (95% CI [0.001, 0.006]) predicted more stress during pregnancy, and childhood maltreatment history interacted with emotion dysregulation to predict resting RSA (95% CI [-0.04, -0.0003]). Exploratory analyses revealed that women's health-related stress during pregnancy mediated the relation between emotion dysregulation and RSA regardless of childhood maltreatment severity (95% CI [-0.007, -0.002]). These findings suggest that women's resting RSA during pregnancy may reflect physical and emotional stress accumulation across the lifespan and that relations between early life adversity and prenatal psychophysiology may be buffered by protective factors, such as emotion regulation. In addition, these findings underscore the importance of distinguishing between types of prenatal stress. Given the implications for women's health and offspring development, we urge researchers to continue exploring factors associated with pregnant women's psychophysiology.

Reduced mechanical function of the left atrial predicts adverse outcome in pregnant women with clustering of metabolic risk factors

INTRODUCTION

The left atrial (LA) strain and strain rate are sensitive indicators of LA function. However, they are not widely used for the evaluation of pregnant women with metabolic diseases. The aim of this study was to assess the LA strain and strain rate of pregnant women with clustering of metabolic risk factors and to explore its prognostic effect on adverse pregnancy outcomes.

MATERIALS AND METHODS

Sixty-three pregnant women with a clustering of metabolic risk factors (CMR group), fifty-seven women with pregnancy-induced hypertension (PIH group), fifty-seven women with gestational diabetes mellitus (GDM group), and fifty matched healthy pregnant women (control group) were retrospectively evaluated. LA function was evaluated with two-dimensional speckle-tracking imaging. Iatrogenic preterm delivery caused by severe preeclampsia, placental abruption, and fetal distress was regarded as the primary adverse outcome.

RESULTS

The CMR group showed the lowest LA strain during reservoir phase (LASr), strain during contraction phase (LASct) and peak strain rate during conduit phase (pLASRcd) among the three groups (P < 0.05). LA strain during conduit phase (LAScd) and peak strain rate during reservoir phase (pLASRr) in the CMR group were lower than those in the control and GDM groups (P < 0.05). Multivariable Cox regression analysis demonstrated systolic blood pressure (HR = 1.03, 95% CI 1.01-1.05, p = 0.001) and LASr (HR = 0.86, 95% CI 0.80-0.92, p < 0.0001) to be independent predictors of iatrogenic preterm delivery. An LASr cutoff value ≤ 38.35% predicted the occurrence of iatrogenic preterm delivery.

CONCLUSIONS

LA mechanical function in pregnant women with metabolic aggregation is deteriorated. An LASr value of 38.35% or less may indicate the occurrence of adverse pregnancy outcomes.

Acute heart failure in pregnancy: Importance of a timely multidisciplinary approach to recognition and management

Increased cardiovascular demands of pregnancy may unmask occult diseases, such as dilated cardiomyopathy or valvular stenosis, or precipitate peripartum cardiomyopathy. We report a case of the emergency management and delivery of a young pregnant woman who presented with acute decompensated heart failure that was not immediately recognized. An emergency transfer to a tertiary care institution was arranged. Once diagnosed, the patient received multidisciplinary care shared between cardiologists, obstetricians, cardiac anesthetists, a neonatologist, and a midwife, resulting in good maternal and fetal outcomes.

Sexual Dimorphism of the Heart: Genetics, Epigenetics, and Development

The democratization of genomic technologies has revealed profound sex biases in expression patterns in every adult tissue, even in organs with no conspicuous differences, such as the heart. With the increasing awareness of the disparities in cardiac pathophysiology between males and females, there are exciting opportunities to explore how sex differences in the heart are established developmentally. Although sexual dimorphism is traditionally attributed to hormonal influence, expression and epigenetic sex biases observed in early cardiac development can only be accounted for by the difference in sex chromosome composition, i.e., XX in females and XY in males. In fact, genes linked to the X and Y chromosomes, many of which encode regulatory factors, are expressed in cardiac progenitor cells and at every subsequent developmental stage. The effect of the sex chromosome composition may explain why many congenital heart defects originating before gonad formation exhibit sex biases in presentation, mortality, and morbidity. Some transcriptional and epigenetic sex biases established soon after fertilization persist in cardiac lineages, suggesting that early epigenetic events are perpetuated beyond early embryogenesis. Importantly, when sex hormones begin to circulate, they encounter a cardiac genome that is already functionally distinct between the sexes. Although there is a wealth of knowledge on the effects of sex hormones on cardiac function, we propose that sex chromosome-linked genes and their downstream targets also contribute to the differences between male and female hearts. Moreover, identifying how hormones influence sex chromosome effects, whether antagonistically or synergistically, will enhance our understanding of how sex disparities are established. We also explore the possibility that sexual dimorphism of the developing heart predicts sex-specific responses to environmental signals and foreshadows sex-biased health-related outcomes after birth.