Association between angiogenic factors and signs of arterial aging in women with pre-eclampsia

Maternal Microvascular Dysfunction During and After Preeclamptic Pregnancy

Preeclampsia, a pregnancy disorder characterized by de novo hypertension and maternal multisystem organ dysfunction, is the leading cause of maternal mortality worldwide and is associated with a fourfold greater risk of cardiovascular disease throughout the lifespan. Current understanding of the etiology of preeclampsia remains unclear, due in part to the varying phenotypical presentations of the disease, which has hindered the development of effective and mechanism-specific treatment or prevention strategies both during and after the affected pregnancy. These maternal sequelae of preeclampsia are symptoms of systemic vascular dysfunction in the maternal nonreproductive microvascular beds that drives the development and progression of adverse cardiovascular outcomes during preeclampsia. Despite normalization of vascular disturbances after delivery, subclinical dysfunction persists in the nonreproductive microvascular beds, contributing to an increased lifetime risk of cardiovascular and metabolic diseases and all-cause mortality. Given that women with a history of preeclampsia demonstrate vascular dysfunction despite an absence of traditional CVD risk factors, an understanding of the underlying mechanisms of microvascular dysfunction during and after preeclampsia is essential to identify potential therapeutic avenues to mitigate or reverse the development of overt disease. This article aims to provide a summary of the existing literature on the pathophysiology of maternal microvascular dysfunction during preeclampsia, the mechanisms underlying the residual dysfunction that remains after delivery, and current and potential treatments both during and after the affected pregnancy that may reduce microvascular dysfunction in these high-risk women. © 2024 American Physiological Society. Compr Physiol 14:5703-5727, 2024.

Metabolic theory of preeclampsia: implications for maternal cardiovascular health

Preeclampsia (PE) is a multisystemic disorder of pregnancy that not only causes perinatal mortality and morbidity but also has a long-term toll on the maternal and fetal cardiovascular system. Women diagnosed with PE are at greater risk for the subsequent development of hypertension, ischemic heart disease, cardiomyopathy, cerebral edema, seizures, and end-stage renal disease. Although PE is considered heterogeneous, inefficient extravillous trophoblast (EVT) migration leading to deficient spiral artery remodeling and increased uteroplacental vascular resistance is the likely initiation of the disease. The principal pathophysiology is placental hypoxia, causing subsequent oxidative stress, leading to mitochondrial dysfunction, mitophagy, and immunological imbalance. The damage imposed on the placenta in turn results in the "stress response" categorized by the dysfunctional release of vasoactive components including oxidative stressors, proinflammatory factors, and cytokines into the maternal circulation. These bioactive factors have deleterious effects on systemic endothelial cells and coagulation leading to generalized vascular dysfunction and hypercoagulability. A better understanding of these metabolic factors may lead to novel therapeutic approaches to prevent and treat this multisystemic disorder. In this review, we connect the hypoxic-oxidative stress and inflammation involved in the pathophysiology of PE to the resulting persistent cardiovascular complications in patients with preeclampsia.

Translation of mechanistic advances in preeclampsia to the clinic: Long and winding road

As one of the leading causes of premature birth and maternal and infant mortality worldwide, preeclampsia remains a major unmet public health challenge. Preeclampsia and related hypertensive disorders of pregnancy are estimated to cause >75 000 maternal and 500 000 infant deaths globally each year. Because of rising rates of risk factors such as obesity, in vitro fertilization and advanced maternal age, the incidence of preeclampsia is going up with rates ranging from 5% to 10% of all pregnancies worldwide. A major discovery in the field was the realization that the clinical phenotypes related to preeclampsia, such as hypertension, proteinuria, and other adverse maternal/fetal events, are due to excess circulating soluble fms-like tyrosine kinase-1 (sFlt-1, also referred to as sVEGFR-1). sFlt-1 is an endogenous anti-angiogenic protein that is made by the placenta and acts by neutralizing the pro-angiogenic proteins vascular endothelial growth factor (VEGF) and placental growth factor (PlGF). During the last decade, this work has spawned a new era of molecular diagnostics for early detection of this condition. Antagonizing sFlt-1 either by reducing production or blocking its actions has shown salutary effects in animal models. Further, in early-stage human studies, the therapeutic removal of sFlt-1 from maternal circulation has shown promise in delaying disease progression and improving outcomes. Recently, the FDA approved the first molecular test for preterm preeclampsia (sFlt-1/PlGF ratio) for clinical use in the United States. Measuring serum sFlt-1/PlGF ratio in the acute hospital setting may aid short-term management, particularly regarding step-up or step-down of care, decision to transfer to settings better equipped to manage both the mother and the preterm neonate, appropriate timing of administration of steroids and magnesium sulfate, and in expectant management decisions. The test itself has the potential to save lives. Furthermore, the availability of a molecular test that correlates with adverse outcomes has set the stage for interventional clinical trials testing treatments for this disorder. In this review, we will discuss the role of circulating sFlt-1 and related factors in the pathogenesis of preeclampsia and specifically how this discovery is leading to concrete advances in the care of women with preeclampsia.

The Importance of Inflammatory and Angiogenic Markers in the Evaluation of Early Cardiovascular Disease Risk in Women with Hypertensive Disorders of Pregnancy

BACKGROUND

Women with hypertensive disorders of pregnancy (HDP) have a significantly higher risk of developing cardiovascular diseases later in life. The stratification of this risk using biomarkers during pregnancy can help to identify these women and apply early prevention.

OBJECTIVE

We aimed to determine proinflammatory cytokines and angiogenic markers, echocardiographic parameter changes after delivery and predict early cardiovascular disease risk in women with arterial hypertension and its complications during pregnancy.

METHODS

We conducted a literature search using the PubMed database for the last ten years. A total of 17 articles were included to our study and full text reviewed.

RESULTS

Four out of six studies found higher postpartum Interleukin-6 (IL-6) levels in women with HDP. IL-6 correlated positively with waist circumference, body mass index, and triglycerides, and negatively with high density lipoproteins (HDL). Two out of four studies found higher postpartum tumor necrosis factor alpha (TNF-α) levels in women with HDP but later concentration equalizes. One out of eight studies found higher placental growth factor (PlGF) and two out of eight found more elevated soluble fms-like tyrosine kinase-1 (sFlt-1) in women with HDP. With decreasing PlGF and increasing sFlt-1, common carotid artery intima and media thickness, aortic root diameter, left atrial diameter, left ventricle mass, systolic, diastolic, and mean blood pressure increased, whereas HDL decreased. One out of four studies found higher sFlt-1/PlGF.

CONCLUSION

IL-6 remains significantly higher after delivery. Few studies found higher TNF-α, sFlt-1, PlGF and their ratio postpartum. All studies found a correlation between angiogenic factors, IL-6, and cardiovascular disease risk factors.

Preeclampsia at term can be classified into 2 clusters with different clinical characteristics and outcomes based on angiogenic biomarkers in maternal blood

BACKGROUND

An antiangiogenic state has emerged as a mechanism of disease in preeclampsia. Angiogenic biomarkers are used in the risk assessment of this syndrome, particularly of early disease. The role of an antiangiogenic state in late preeclampsia is unclear.

OBJECTIVE

This study aimed to determine the prevalence, characteristics, and clinical significance of angiogenic/antiangiogenic factor abnormalities in women with preeclampsia stratified according to gestational age at delivery.

STUDY DESIGN

Two studies were conducted: (1) a longitudinal nested case-control study comprising women with preeclampsia (n=151) and a control group (n=540); and (2) a case series of patients with preeclampsia (n=452). In patients with preeclampsia, blood was collected at the time of diagnosis. Plasma concentrations of placental growth factor and soluble fms-like tyrosine kinase-1 were determined by enzyme-linked immunosorbent assays. An abnormal angiogenic profile was defined as a plasma ratio of placental growth factor and soluble fms-like tyrosine kinase-1 expressed as a multiple of the median <10th percentile for gestational age based on values derived from the longitudinal study. The proportion of patients diagnosed with preeclampsia who had an abnormal angiogenic profile was determined in the case-series participants and stratified by gestational age at delivery into early (≤34 weeks), intermediate (34.1-36.9 weeks), and term (≥37 weeks) preeclampsia. The demographics, clinical characteristics, and pregnancy outcomes of women with preeclampsia with and without an abnormal angiogenic profile were compared.

RESULTS

The prevalence of an abnormal angiogenic profile was higher in preterm than in term preeclampsia (for early, intermediate, and term in the case-control study: 90%, 100%, and 39%; for the case series: 98%, 80%, and 55%, respectively). Women with preeclampsia at term who had an abnormal angiogenic profile were more frequently nulliparous (57% vs 35%), less likely to smoke (14% vs 26%), at greater risk for maternal (14% vs 5%) or neonatal (7% vs 1%) complications, and more often had placental lesions consistent with maternal vascular malperfusion (42% vs 23%; all, P<.05) than those without an abnormal profile. Women with preeclampsia at term who had a normal angiogenic profile had a higher frequency of chronic hypertension (36% vs 21%) and were more likely to have class ≥2 obesity (41% vs 23%) than those with an abnormal profile (both, P<.05).

CONCLUSION

Patients with early preeclampsia had an abnormal angiogenic profile in virtually all cases, whereas only 50% of women with preeclampsia at term had such abnormalities. The profile of angiogenic biomarkers can be used to classify patients with preeclampsia at term, on the basis of mechanisms of disease, into 2 clusters, which have different demographics, clinical characteristics, and risks of adverse maternal and neonatal outcomes. These findings provide a simple approach to classify preeclampsia at term and have implications for future clinical care and research.

Literature Review: The sFlt1/PlGF Ratio and Pregestational Maternal Comorbidities: New Risk Factors to Predict Pre-Eclampsia

One of the main causes of maternal and neonatal morbidity and mortality is pre-eclampsia. It is characterized by a high sFlt1/PlGF ratio, according to prior research. Pregestational diseases in mothers may increase the risk of developing pre-eclampsia. Only a few studies have looked at the connection between maternal comorbidities before conception and the sFlt1/PlGF ratio. The most recent information regarding the association between maternal pregestational diseases and the ratio of sFlt1/PlGF is described in this review. The paper also examines current research suggesting that changes in pregnancy hormones and metabolites are related to a high sFlt1/PlGF ratio. Certain maternal disorders have been found to dramatically raise sFlt-1 and sFlt1/PlGF levels, according to an analysis of the literature. There is still debate about the data on the association between the sFlt1/PlGF ratio and maternal disorders such as HIV, acute coronary syndromes, cardiovascular function in the mother between 19 and 23 weeks of pregnancy, thyroid hormones, diabetes, and cancer. Additional research is needed to confirm these findings.

Smooth Muscle Mineralocorticoid Receptor Promotes Hypertension After Preeclampsia

BACKGROUND

Preeclampsia is a syndrome of high blood pressure (BP) with end organ damage in late pregnancy that is associated with high circulating soluble VEGF receptor (sFlt1 [soluble Fms-like tyrosine kinase 1]). Women exposed to preeclampsia have a substantially increased risk of hypertension after pregnancy, but the mechanism remains unknown, leaving a missed interventional opportunity. After preeclampsia, women have enhanced sensitivity to hypertensive stress. Since smooth muscle cell mineralocorticoid receptors (SMC-MR) are activated by hypertensive stimuli, we hypothesized that high sFlt1 exposure in pregnancy induces a postpartum state of enhanced SMC-MR responsiveness.

METHODS

Postpartum BP response to high salt intake was studied in women with prior preeclampsia. MR transcriptional activity was assessed in vitro in sFlt1-treated SMC by reporter assays and PCR. Preeclampsia was modeled by transient sFlt1 expression in pregnant mice. Two months post-partum, mice were exposed to high salt and then to AngII (angiotensin II) and BP and vasoconstriction were measured.

RESULTS

Women exposed to preeclampsia had significantly enhanced salt sensitivity of BP verses those with a normotensive pregnancy. sFlt1 overexpression during pregnancy in mice induced elevated BP and glomerular endotheliosis, which resolved post-partum. The sFlt1 exposed post-partum mice had significantly increased BP response to 4% salt diet and to AngII infusion. In vitro, SMC-MR transcriptional activity in response to aldosterone or AngII was significantly increased after transient exposure to sFlt1 as was aldosterone-induced expression of AngII type 1 receptor. Post-partum, SMC-MR-KO mice were protected from the enhanced response to hypertensive stimuli after preeclampsia. Mechanistically, preeclampsia mice exposed to postpartum hypertensive stimuli develop enhanced aortic stiffness, microvascular myogenic tone, AngII constriction, and AngII type 1 receptor expression, all of which were prevented in SMC-MR-KO littermates.

CONCLUSIONS

These data support that sFlt1-induced vascular injury during preeclampsia produces a persistent state of enhanced sensitivity of SMC-MR to activation. This contributes to postpartum hypertension in response to common stresses and supports testing of MR antagonism to mitigate the increased cardiovascular risk in women after PE.

Peripheral Vascular Ageing in Pulmonary Arterial Hypertension as Assessed by Common Carotid Artery Intima Thickness and Intima/Media Thickness Ratio: An Investigation Using Non-Invasive High-Resolution Ultrasound

BACKGROUND

Pulmonary arterial hypertension (PAH; World Heath Organization [WHO] Group 1) is associated with increased pulmonary arterial pressure and resistance, with pulmonary vascular remodelling. The vascular anatomy of the systemic arteries has been less well studied.

METHOD

Nineteen (19) patients with PAH, confirmed by right heart catheterisation (RHC), 14 patients with left ventricular heart failure with reduced ejection fraction (LVrEF), and 30 healthy subjects were enrolled. Common carotid artery (CCA) intima thickness, intima/media (I/M) thickness ratio, and intima-media thickness (IMT) were assessed using non-invasive ultrasound (22 MHz centre frequency).

RESULTS

The CCA intima thickness was correlated with several RHC variables (all p<0.05). The intima was 56% thicker (+0.05 mm; 95% CI 0.03, 0.06; p<0.0001) and the I/M thickness ratio was 128% greater (+0.21; 95% CI 0.13, 0.28; p<0.0001) in patients with PAH than healthy subjects. These values were also significantly higher than in patients with LVrEF. In ROC curve analysis, the c-values for CCA intima thickness (0.92) and I/M ratio (0.87), but not for IMT, correctly indicated which individuals belonged to the PAH or healthy control groups. The CCA IMT showed no corresponding significant group differences or associations and was of no use according to receiver operating curve analysis.

CONCLUSIONS

Patients with PAH displayed signs of peripheral vascular remodelling, challenging the common opinion that vascular changes in PAH are restricted to the lung vasculature. Correlations with cardiopulmonary variables from RHC support peripheral vascular coupling and the association with vascular ageing. Results from this pilot study warrant further confirmation.

Prevalence of pre-eclampsia and adverse pregnancy outcomes in women with pre-existing cardiomyopathy: a multi-centre retrospective cohort study

Pre-eclampsia is associated with postnatal cardiac dysfunction; however, the nature of this relationship remains uncertain. This multicentre retrospective cohort study aimed to determine the prevalence of pre-eclampsia in women with pre-existing cardiac dysfunction (left ventricular ejection fraction < 55%) and explore the relationship between pregnancy outcome and pre-pregnancy cardiac phenotype. In this cohort of 282 pregnancies, pre-eclampsia prevalence was not significantly increased (4.6% [95% C.I 2.2-7.0%] vs. population prevalence of 4.6% [95% C.I. 2.7-8.2], p = 0.99); 12/13 women had concurrent obstetric/medical risk factors for pre-eclampsia. The prevalence of preterm pre-eclampsia (< 37 weeks) and fetal growth restriction (FGR) was increased (1.8% vs. 0.7%, p = 0.03; 15.2% vs. 5.5%, p < 0.001, respectively). Neither systolic nor diastolic function correlated with pregnancy outcome. Antenatal ß blockers (n = 116) were associated with lower birthweight Z score (adjusted difference - 0.31 [95% C.I. - 0.61 to - 0.01], p = 0.04). To conclude, this study demonstrated a modest increase in preterm pre-eclampsia and significant increase in FGR in women with pre-existing cardiac dysfunction. Our results do not necessarily support a causal relationship between cardiac dysfunction and pre-eclampsia, especially given the population's background risk status. The mechanism underpinning the relationship between cardiac dysfunction and FGR merits further research but could be influenced by concomitant ß blocker use.

Maternal Cardiovascular Function Following a Pregnancy Complicated by Preeclampsia

Preeclampsia is a hypertensive pregnancy complication with an unknown etiology and high maternal burden worldwide. Burgeoning research has linked preeclampsia to adverse maternal health outcomes remote from pregnancy; however, the intermediary mechanisms responsible for this association have not been sufficiently established. In the present narrative review, we summarize leading evidence of structural and functional cardiovascular changes associated with prior preeclampsia, and how these changes may be linked to future maternal disease. KEY POINTS: · Prior preeclampsia is associated with subclinical structural and functional vascular changes remote from pregnancy.. · Maternal cardiac adaptations to preeclampsia may have long-term implications on cardiovascular health.. · Clinicians have an opportunity to minimize maternal disease risk following preeclampsia..

Placental Pathology as a Tool to Identify Women for Postpartum Cardiovascular Risk Screening following Preeclampsia: A Preliminary Investigation

Preeclampsia (PE) is associated with an increased risk of cardiovascular disease (CVD) in later life. Postpartum cardiovascular risk screening could identify patients who would benefit most from early intervention and lifestyle modification. However, there are no readily available methods to identify these high-risk women. We propose that placental lesions may be useful in this regard. Here, we determine the association between placental lesions and lifetime CVD risk assessed 6 months following PE. Placentas from 85 PE women were evaluated for histopathological lesions. At 6 months postpartum, a lifetime cardiovascular risk score was calculated. Placental lesions were compared between CVD risk groups and the association was assessed using odds ratios. Multivariable logistic regression was used to develop prediction models for CVD risk with placental pathology. Placentas from high-risk women had more severe lesions of maternal vascular malperfusion (MVM) and resulted in a 3-fold increased risk of screening as high-risk for CVD (OR 3.10 (1.20–7.92)) compared to women without these lesions. MVM lesion severity was moderately predictive of high-risk screening (AUC 0.63 (0.51, 0.75); sensitivity 71.8% (54.6, 84.4); specificity 54.7% (41.5, 67.3)). When clinical parameters were added, the model’s predictive performance improved (AUC 0.73 (0.62, 0.84); sensitivity 78.4% (65.4, 87.5); specificity 51.6% (34.8, 68.0)). The results suggest that placenta pathology may provide a unique modality to identify women for cardiovascular screening.

Novel Cardiovascular Biomarkers Associated with Increased Cardiovascular Risk in Women With Prior Preeclampsia/HELLP Syndrome: A Narrative Review

Evidence has shown that women with a history of preeclampsia or haemolysis, elevated liver enzymes and low platelets (HELLP) syndrome have an increased risk of cardiovascular disease later in life. Recommendations for screening, prevention and management after such pregnancies are not yet defined. The identification of promising non-traditional cardiovascular biomarkers might be useful to predict which women are at greatest risk. Many studies are inconsistent and an overview of the most promising biomarkers is currently lacking. This narrative review provides an update of the current literature on circulating cardiovascular biomarkers that may be associated with an increased cardiovascular disease risk in women after previous preeclampsia/HELLP syndrome. Fifty-six studies on 53 biomarkers were included. From the summary of evidence, soluble fms-like tyrosine kinase-1, placental growth factor, interleukin (IL)-6, IL-6/IL-10 ratio, high-sensitivity cardiac troponin I, activin A, soluble human leukocyte antigen G, pregnancy-associated plasma protein A and norepinephrine show potential and are interesting candidate biomarkers to further explore. These biomarkers might be potentially eligible for cardiovascular risk stratification after preeclampsia/HELLP syndrome and may contribute to the development of adequate strategies for prevention of hypertension and adverse events in this population.

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.

Dimethylarginines correlate to common carotid artery wall layer dimensions and cardiovascular risk factors in pregnant women with/without preeclampsia: A group comparative study

OBJECTIVES

Asymmetric- and symmetric dimethylarginines (ADMA, SDMA) are elevated in cardiovascular disease (CVD). Preeclampsia is a pregnancy-specific syndrome and is an independent risk factor for subsequent CVD. Aims were to investigate whether ADMA, SDMA levels and l-arginine/ADMA and l-arginine/SDMA ratios during pregnancy and their changes from pregnancy to postpartum are associated to arterial wall layer dimensions and cardiovascular risk factors in women with and without preeclampsia.

STUDY DESIGN

Dimethylarginines were analyzed by LC-MS, and the common-carotid-artery (CCA) intima and media thicknesses were estimated using 22-MHz non-invasive ultrasonography in women with preeclampsia (cases = 48) and normal pregnancies (controls = 58) in similar gestational age, with reassessment one-year postpartum. A thick intima, thin media and high intima/media ratio (I/M) indicates a less healthy arterial wall.

RESULTS

The median age of cases and controls was 30 years. During pregnancy, women with preeclampsia had higher plasma ADMA, SDMA and lower l-arginine/ADMA and l-arginine/SDMA (all p < 0.01) than women with normal pregnancies. Further, ADMA, SDMA, l-arginine/ADMA and l-arginine/SDMA correlated to intima thickness (r_s = 0.33/0.33/-0.33/-0.35 and p < 0.01), I/M (r_s = 0.26/0.28/-0.22/-0.26 and p < 0.05) and mean arterial pressure (MAP) (r_s = 0.43/0.42/-0.39/-0.40 and p < 0.0001). Changes in ADMA, SDMA and l-arginine/SDMA from pregnancy to postpartum correlated to changes in intima thickness (r_s = 0.22/0.32/-0.21 and p < 0.05/<0.01/<0.05), I/M (r_s = 0.22/0.31/0.08 and p < 0.05/<0.01/=0.43) and MAP (r_s = 0.31/0.53/-0.25 and p < 0.01/<0.001/<0.05). No correlations were found for conventional CCA intima-media-thickness.

CONCLUSIONS

Dimethylarginines were associated to signs of adverse effects on arterial wall layer dimensions and cardiovascular risk factors in women with and without preeclampsia, during pregnancy and to their changes from pregnancy up to one-year postpartum.

Biomarkers and Their Relation to Cardiac Function Late After Peripartum Cardiomyopathy

BACKGROUND

Angiogenic imbalance involving the placental protein soluble Fms-like tyrosine kinase-1 (sFlt-1) and cleavage of the nursing-hormone prolactin by the enzyme cathepsin D (CD) both play a role in the pathogenesis of peripartum cardiomyopathy (PPCM). We hypothesized that angiogenic imbalance and increased activity of CD have a long-lasting impact in women with PPCM.

METHODS AND RESULTS

A nationwide Danish cohort of women with PPCM (PPCM group, n = 28), age matched women with previous preeclampsia (n = 28) and uncomplicated pregnancies (n = 28) participated in a follow-up study including biomarker analysis, exercise testing and cardiac magnetic resonance imaging. The median time to follow-up was 91 months (range 27-137 months) for the PPCM group. Levels of sFlt-1, placental growth factor, N-terminal pro-natriuretic brain peptide, and copeptin were all significantly higher in the PPCM group. More women in the PPCM group had detectable CD activity (68%) compared with the preeclampsia group (29%) and uncomplicated pregnancies group (36%) (P = .0002). Levels of angiogenic factors and biomarkers correlated inversely with maximal exercise capacity and cardiac functional parameters assessed with cardiac magnetic resonance imaging.

CONCLUSIONS

Women with PPCM had higher biomarker levels and CD activity up to 7 years after diagnosis. Higher biomarker levels correlated inversely with maximal exercise capacity and markers of cardiac dysfunction suggesting that persistent angiogenic imbalance and increased CD activity is associated with residual cardiac dysfunction.

MZe786 Rescues Cardiac Mitochondrial Activity in High sFlt-1 and Low HO-1 Environment

Hypertensive disorder in pregnancy is a major cause of maternal and perinatal mortality worldwide. Women who have had preeclampsia are at three to four times higher risk in later life of developing high blood pressure and heart disease. Soluble Flt-1 (sFlt-1) is elevated in preeclampsia and may remain high postpartum in women with a history of preeclampsia. Heme oxygenase-1 (Hmox1/HO-1) exerts protective effects against oxidative stimuli and is compromised in the placenta of pregnant women with preeclampsia. We hypothesized that sFlt-1 inhibits cardiac mitochondrial activity in HO-1 deficient mice. HO-1 haplo-insufficient mice (Hmox1^+/−) were injected with adenovirus encoding sFlt-1 (Ad-sFlt-1) or control virus (Ad-CMV). Subsequently, they were treated daily with either placebo or MZe786 for six days, when the heart tissue was harvested to assess cardiac mitochondrial activity. Here, we show that the loss of HO-1 disturbed cardiac mitochondrial respiration and reduced mitochondrial biogenesis. The overexpression of sFlt-1 resulted in the inhibition of the cardiac mitochondrial activity in Hmox1^+/− mice. The present study demonstrates that the hydrogen sulfide (H₂S) releasing molecule, MZe786, rescues mitochondrial activity by stimulating cardiac mitochondrial biogenesis and antioxidant defense in Hmox1^−/− mice and in Hmox1^+/− mice exposed to a high sFlt-1 environment.

Preeclampsia: Maternal Systemic Vascular Disorder Caused by Generalized Endothelial Dysfunction Due to Placental Antiangiogenic Factors

Preeclampsia, a systemic vascular disorder characterized by new-onset hypertension and proteinuria after 20 weeks of gestation, is the leading cause of maternal and perinatal morbidity and mortality. Maternal endothelial dysfunction caused by placental factors has long been accepted with respect to the pathophysiology of preeclampsia. Over the past decade, increased production of placental antiangiogenic factors has been identified as a placental factor leading to maternal endothelial dysfunction and systemic vascular dysfunction. This review summarizes the recent advances in understanding the molecular mechanisms of endothelial dysfunction caused by placental antiangiogenic factors, and the novel clinical strategies based on these discoveries.

Cardiovascular origins of preeclampsia

PURPOSE OF REVIEW

To review the current data on maternal cardiovascular adaptation in normal pregnancy and preeclampsia.

RECENT FINDINGS

Defective placentation causes early-onset preeclampsia, a disease entity that is considered more or less distinct from late-onset preeclampsia. The latter has been attributed as 'maternal' preeclampsia. There are inconsistencies with the placental origins hypothesis, especially when considering the lack of a causative association with abnormal placental histology or impaired fetal growth. An alternative explanation is that placental dysfunction is secondary to maternal cardiovascular maladaptation in pregnancy. The concept that placental dysfunction is secondary to a maternal disorder is not new when one considers the clinical similarities between preeclampsia and gestational diabetes - both pregnancy-specific conditions that are cured by birth. It is accepted that gestational diabetes develops when the maternal pancreas is unable to manage the increasing glucose load of pregnancy. It is now apparent that pregnancy presents a substantial cardiovascular load on the maternal heart, and that cardiovascular dysfunction precedes the disorder, predominates in the clinical syndrome and persists for several decades postpartum. It is time to consider the evidence that failure of the maternal cardiovascular system to adapt to pregnancy may well be the primary mechanism leading to secondary placental dysfunction in preeclampsia.

SUMMARY

Many of the existing paradoxes of preeclampsia challenge the placental origin hypothesis and are explained if one considered preeclampsia to be a cardiovascular syndrome.

Vascular Dysfunction in Mother and Offspring During Preeclampsia: Contributions from Latin-American Countries

Pregnancy is a physiologically stressful condition that generates a series of functional adaptations by the cardiovascular system. The impact of pregnancy on this system persists from conception beyond birth. Recent evidence suggests that vascular changes associated with pregnancy complications, such as preeclampsia, affect the function of the maternal and offspring vascular systems, after delivery and into adult life. Since the vascular system contributes to systemic homeostasis, defective development or function of blood vessels predisposes both mother and infant to future risk for chronic disease. These alterations in later life range from fertility problems to alterations in the central nervous system or immune system, among others. It is important to note that rates of morbi-mortality due to pregnancy complications including preeclampsia, as well as cardiovascular diseases, have a higher incidence in Latin-American countries than in more developed countries. Nonetheless, there is a lack both in the amount and impact of research conducted in Latin America. An impact, although smaller, can be seen when research in vascular disorders related to problems during pregnancy is analyzed. Therefore, in this review, information about preeclampsia and endothelial dysfunction generated from research groups based in Latin-American countries will be highlighted. We relate the need, as present in many other countries in the world, for increased effective regional and international collaboration to generate new data specific to our region on this topic.

The influence of prenatal exercise and pre-eclampsia on maternal vascular function

During healthy pregnancy, the cardiovascular system undergoes diverse adaptations to support adequate transfer of oxygen and nutrients from mother to fetus. In order to accommodate the large expansion of blood volume and associated cardiac output, the structure, mechanics, and function of the arteries are altered. Specifically, in healthy pregnancy there is a remodeling of arteries (increased angiogenesis and vasodilation), a generalized reduction in arterial stiffness (increased compliance), and an enhanced endothelial function. The development of pregnancy complications, specifically pre-eclampsia, is associated with poor placentation (decreased angiogenesis), increased arterial stiffness, and vascular dysfunction (reduced endothelial function). Many of the positive adaptations that occur in healthy pregnancy are enhanced in response to chronic exercise. Specifically, placental angiogenesis and endothelial function have been shown to improve to a greater extent in women who are active during their pregnancy compared with those who are not. Prenatal exercise may be important in helping to reduce the risk of vascular dysfunction in pregnancy. However, our knowledge of the vascular adaptations resulting from maternal exercise is limited. This review highlights maternal vascular adaptations occurring during healthy pregnancy, and contrasts the vascular maladaptation associated with pre-eclampsia. Finally, we discuss the role of prenatal exercise on vascular function in the potential prevention of vascular complications associated with pre-eclampsia.

Pathophysiology of preeclampsia: an angiogenic imbalance and long-lasting systemic vascular dysfunction

Preeclampsia is a systemic vascular disorder characterized by new-onset hypertension and proteinuria after 20 weeks of gestation. This condition targets several organs, including the kidneys, liver and brain, and is the leading cause of maternal and perinatal morbidity and mortality. Furthermore, recent evidence has revealed preeclampsia as a significant risk factor for future cardiovascular diseases in these women. Over the past decade, increasing evidence has indicated that maternal angiogenic imbalances caused by placental antiangiogenic factors play a central role in the systemic vascular dysfunction underling preeclampsia. The severity of the maternal antiangiogenic state correlates closely with maternal and perinatal outcomes. Assessing angiogenic imbalance and several vascular function tests have also emerged as a way of detecting systemic vascular dysfunction during pregnancy. This review summarizes the current understanding of the pathophysiology of preeclampsia, its clinical applications and clinical evidence for future cardiovascular risks.