The relation of arterial stiffness with intrauterine growth retardation

Understanding changes in echocardiographic parameters at different ages following fetal growth restriction: a systematic review and meta-analysis

Fetal growth restriction (FGR) increases cardiovascular risk by cardiac remodeling and programming. This systematic review and meta-analysis across species examines the use of echocardiography in FGR offspring at different ages. PubMed and Embase.com were searched for animal and human studies reporting on echocardiographic parameters in placental insufficiency-induced FGR offspring. We included six animal and 49 human studies. Although unable to perform a meta-analysis of animal studies because of insufficient number of studies per individual outcome, all studies showed left ventricular dysfunction. Our meta-analyses of human studies revealed a reduced left ventricular mass, interventricular septum thickness, mitral annular peak velocity, and mitral lateral early diastolic velocity at neonatal age. No echocardiographic differences during childhood were observed, although the small age range and number of studies limited these analyses. Only two studies at adult age were performed. Meta-regression on other influential factors was not possible due to underreporting. The few studies on myocardial strain analysis showed small changes in global longitudinal strain in FGR offspring. The quality of the human studies was considered low and the risk of bias in animal studies was mostly unclear. Echocardiography may offer a noninvasive tool to detect early signs of cardiovascular predisposition following FGR. Clinical implementation yet faces multiple challenges including identification of the most optimal timing and the exact relation to long-term cardiovascular function in which echocardiography alone might be limited to reflect a child's vascular status. Future research should focus on myocardial strain analysis and the combination of other (non)imaging techniques for an improved risk estimation.NEW & NOTEWORTHY Our meta-analysis revealed echocardiographic differences between fetal growth-restricted and control offspring in humans during the neonatal period: a reduced left ventricular mass and interventricular septum thickness, reduced mitral annular peak velocity, and mitral lateral early diastolic velocity. We were unable to pool echocardiographic parameters in animal studies and human adults because of an insufficient number of studies per individual outcome. The few studies on myocardial strain analysis showed small preclinical changes in FGR offspring.

Impact of perinatal factors on biomarkers of cardiovascular disease risk in preadolescent children

BACKGROUND

This review aims to summarize associations of the perinatal environment with arterial biophysical properties in childhood, to elucidate possible perinatal origins of adult cardiovascular disease (CVD).

METHODS

A systematic search of PubMed database was performed (December 2020). Studies exploring associations of perinatal factors with arterial biophysical properties in children 12 years old or less were included. Properties studied included: pulse wave velocity; arterial stiffness or distensibility; augmentation index; intima-media thickness of aorta (aIMT) or carotids; endothelial function (laser flow Doppler, flow-mediated dilatation). Two reviewers independently performed study selection and data extraction.

RESULTS

Fifty-two of 1084 identified records were included. Eleven studies explored associations with prematurity, 14 explored maternal factors during pregnancy, and 27 explored effects of low birth weight, small-for-gestational age and foetal growth restriction (LBW/SGA/FGR). aIMT was consistently higher in offspring affected by LBW/SGA/FGR in all six studies examining this variable. The cause of inconclusive or conflicting associations found with other arterial biophysical properties and perinatal factors may be multifactorial: in particular, measurements and analyses of related properties differed in technique, equipment, anatomical location, and covariates used.

CONCLUSION

aIMT was consistently higher in LBW/SGA/FGR offspring, which may relate to increased long-term CVD risk. Larger and longer term cohort studies may help to elucidate clinical significance, particularly in relation to established CVD risk factors. Experimental studies may help to understand whether lifestyle or medical interventions can reverse perinatal changes aIMT. The field could be advanced by validation and standardization of techniques assessing arterial structure and function in children.

Fetal endothelial colony-forming cell impairment after maternal kidney transplantation

BACKGROUND

Successful pregnancies are nowadays possible after kidney transplantation but are associated with a higher incidence of maternal and fetal complications. Immunosuppressive therapy causes cardiovascular side effects but must be maintained during pregnancy. Little is known about the consequences of maternal kidney transplantation on offspring's endothelial health. Endothelial colony forming cells (ECFCs) represent a highly proliferative subtype of endothelial progenitor cells and are crucial for vascular homeostasis, repair and neovascularization. Therefore, we investigated whether maternal kidney transplantation affects fetal ECFCs' characteristics.

METHODS

ECFCs were isolated from umbilical cord blood of uncomplicated and post-kidney-transplant pregnancies and analyzed for their functional abilities with proliferation, cell migration, centrosome orientation and angiogenesis assays. Further, ECFCs from uncomplicated pregnancies were exposed to either umbilical cord serum from uncomplicated or post-kidney-transplant pregnancies.

RESULTS

Post-kidney-transplant ECFCs showed significantly less proliferation, less migration and less angiogenesis compared to control ECFCs. The presence of post-kidney-transplant umbilical cord serum led to similar functional aberrations of ECFCs from uncomplicated pregnancies.

CONCLUSIONS

These pilot data demonstrate differences in ECFCs' biological characteristics in offspring of women after kidney transplantation. Further studies are needed to monitor offspring's long-term cardiovascular development and to assess possible causal relationships with immunosuppressants, uremia and maternal cardiovascular alterations.

IMPACT

Pregnancy after kidney transplantation has become more common in the past years but is associated with higher complications for mother and offspring. Little is known of the impact of maternal kidney transplantation and the mandatory immunosuppressive therapy on offspring vascular development. In this study we are the first to address and detect an impairment of endothelial progenitor cell function in offspring of kidney-transplanted mothers. Serum from post-transplant pregnancies also causes negative effects on ECFCs' function. Clinical studies should focus on long-term monitoring of offspring's cardiovascular health.

Fetal growth restriction followed by very preterm birth is associated with smaller kidneys but preserved kidney function in adolescence

BACKGROUND

Preterm birth and fetal growth restriction (FGR) are associated with structural and functional kidney changes, increasing long-term risk for chronic kidney disease and hypertension. However, recent studies in preterm children are conflicting, indicating structural changes but normal kidney function. This study therefore assessed kidney structure and function in a cohort of adolescents born very preterm with and without verified FGR.

METHODS

Adolescents born very preterm with FGR and two groups with appropriate birthweight (AGA) were included; one matched for gestational week at birth and one born at term. Cortical and medullary kidney volumes and T1 and T2* mapping values were assessed by magnetic resonance imaging. Biochemical markers of kidney function and renin-angiotensin-aldosterone system (RAAS) activation were analyzed.

RESULTS

Sixty-four adolescents were included (13-16 years; 48% girls). Very preterm birth with FGR showed smaller total (66 vs. 75 ml/m²; p = 0.01) and medullary volume (19 vs. 24 ml/m²; p < 0.0001) compared to term AGA. Corticomedullary volume ratio decreased from preterm FGR (2.4) to preterm AGA (2.2) to term AGA (1.9; p = 0.004). There were no differences in T1 or T2* values (all p ≥ 0.34) or in biochemical markers (all p ≥ 0.12) between groups.

CONCLUSIONS

FGR with abnormal fetal blood flow followed by very preterm birth is associated with smaller total kidney and medullary kidney volumes, but not with markers of kidney dysfunction or RAAS activation in adolescence. Decreased total kidney and medullary volumes may still precede a long-term decrease in kidney function, and potentially be used as a prognostic marker. A higher resolution version of the Graphical abstract is available as Supplementary information.

Higher blood pressure in adolescent boys after very preterm birth and fetal growth restriction

BACKGROUND

Although preterm birth predisposes for cardiovascular disease, recent studies in children indicate normal blood pressure and arterial stiffness. This prospective cohort study therefore assessed blood pressure and arterial stiffness in adolescents born very preterm due to verified fetal growth restriction (FGR).

METHODS

Adolescents (14 (13-17) years; 52% girls) born very preterm with FGR (preterm FGR; n = 24) and two control groups born with appropriate birth weight (AGA), one in similar gestation (preterm AGA; n = 27) and one at term (term AGA; n = 28) were included. 24-hour ambulatory blood pressure and aortic pulse wave velocity (PWV) and distensibility by magnetic resonance imaging were acquired.

RESULTS

There were no group differences in prevalence of hypertension or in arterial stiffness (all p ≥ 0.1). In boys, diastolic and mean arterial blood pressures increased from term AGA to preterm AGA to preterm FGR with higher daytime and 24-hour mean arterial blood pressures in the preterm FGR as compared to the term AGA group. In girls, no group differences were observed (all p ≥ 0.1).

CONCLUSIONS

Very preterm birth due to FGR is associated with higher, yet normal blood pressure in adolescent boys, suggesting an existing but limited impact of very preterm birth on cardiovascular risk in adolescence, enhanced by male sex and FGR.

IMPACT

Very preterm birth due to fetal growth restriction was associated with higher, yet normal blood pressure in adolescent boys. In adolescence, very preterm birth due to fetal growth restriction was not associated with increased thoracic aortic stiffness. In adolescence, very preterm birth in itself showed an existing but limited effect on blood pressure and thoracic aortic stiffness. Male sex and fetal growth restriction enhanced the effect of preterm birth on blood pressure in adolescence. Male sex and fetal growth restriction should be considered as additional risk factors to that of preterm birth in cardiovascular risk stratification.

Intrauterine growth restriction results in persistent vascular mismatch in adulthood

KEY POINTS

Intrauterine growth restriction (IUGR) increases offspring risk of chronic diseases later in life, including cardiovascular dysfunction. Our prior studies suggest biventricular cardiac dysfunction and vascular impairment in baboons who were IUGR at birth because of moderate maternal nutrient reduction. The current study reveals changes in artery sizes, distensibility, and blood flow pattern in young adult IUGR baboons, which may contribute to cardiac stress. The pattern of abnormality observed suggests that vascular redistribution seen with IUGR in fetal life may continue into adulthood.

ABSTRACT

Maternal nutrient reduction induces intrauterine growth restriction (IUGR), increasing risks of chronic diseases later in life, including cardiovascular dysfunction. Using ultrasound, we determined regional blood flow, blood vessel sizes, and distensibility in IUGR baboons (8 males, 8 females, 8.8 years, similar to 35 human years) and controls (12 males, 12 females, 9.5 years). The measured blood vessels were larger in size in the males compared to females before but not after normalization to body surface area. Smaller IUGR normalized blood vessel sizes were observed in the femoral and external iliac arteries but not the brachial or common carotid arteries and not correlated significantly with birth weight. Mild decrease in distensibility in the IUGR group was seen in the iliac but not the carotid arteries without between-sex differences. In IUGR baboons there was increased carotid arterial blood flow velocity during late systole and diastole. Overall, our findings support the conclusion that region specific vascular and haemodynamic changes occur with IUGR, which may contribute to the occurrence of later life cardiac dysfunction. The pattern of alteration observed suggests vascular redistribution efforts in response to challenges in the perinatal period may persist into adulthood. Further studies are needed to determine the life course progression of these changes.

In Development-A New Paradigm for Understanding Vascular Disease

Under physiological conditions, the arterial endothelium exerts a powerful protective influence to maintain vascular homeostasis. However, during the development of vascular disease, these protective activities are lost, and dysfunctional endothelial cells actually promote disease pathogenesis. Numerous investigations have analyzed the characteristics of dysfunctional endothelium with a view to understanding the processes responsible for the dysfunction and to determining their role in vascular pathology. This review adopts an alternate approach: reviewing the mechanisms that contribute to the initial formation of a healthy protective endothelium and on how those mechanisms may be disrupted, precipitating the appearance of dysfunctional endothelial cells and the progression of vascular disease. This approach, which highlights the role of endothelial adherens junctions and vascular endothelial-cadherin in endothelial maturation and endothelial dysfunction, provides new insight into the remarkable biology of this important cell layer and its role in vascular protection and vascular disease.

Myocardial dysfunction in children with intrauterine growth restriction: an echocardiographic study

Introduction

The prevalence of intrauterine growth restriction (IUGR) is about 3–10% of live-born newborns and can be as high as 20% in developing countries. It may result in the occurrence of cardiovascular diseases later in life.

Methods

The aim of this study was echocardiographic evaluation, with the use of conventional and tissue Doppler parameters, of cardiac function in children born with IUGR, and comparison with healthy peers born as normally grown foetuses.

Results

In the IUGR group, E wave and E/A ratio were significantly lower compared to the control group. A wave, isovolumetric relaxation time, deceleration time, myocardial performance index as well as E/E′ septal and E/E′ lateral indices were significantly higher compared to healthy peers.

Conclusion

Children with IUGR presented with subclinical myocardial dysfunction.

Maternal undernutrition and cardiometabolic disease: a Latin American perspective

The current epidemic of obesity and cardiometabolic diseases in developing countries is described as being driven by socioeconomic inequalities. These populations have a greater vulnerability to cardiometabolic diseases due to the discrepancy between the maternal undernutrition and its consequence, low-birth weight progeny, and the subsequent modern lifestyles which are associated with socioeconomic and environmental changes that modify dietary habits, discourage physical activity and encourage sedentary behaviors. Maternal undernutrition can generate epigenetic modifications, with potential long-term consequences. Throughout life, people are faced with the challenge of adapting to changes in their environment, such as excessive intake of high energy density foods and sedentary behavior. However, a mismatch between conditions experienced during fetal programming and current environmental conditions will make adaptation difficult for them, and will increase their susceptibility to obesity and cardiovascular diseases. It is important to conduct research in the Latin American context, in order to define the best strategies to prevent the epidemic of cardiometabolic diseases in the region.

Intrauterine nutrition: long-term consequences for vascular health

There is a growing body of evidence that improper intrauterine nutrition may negatively influence vascular health in later life. Maternal malnutrition may result in intrauterine growth retardation and, in turn, metabolic disorders such as insulin resistance, diabetes, hypertension, and dyslipidemia, and also enhanced risk of atherosclerosis and cardiovascular death in the offspring. Energy and/or protein restriction is the most critical determinant for fetal programming. However, it has also been proposed that intrauterine n-3 fatty acid deficiency may be linked to later higher blood pressure levels and reduced insulin sensitivity. Moreover, it has been shown that inadequate supply of micronutrients such as folate, vitamin B12, vitamin A, iron, magnesium, zinc, and calcium may contribute to impaired vascular health in the progeny. In addition, hypertensive disorders of pregnancy that are linked to impaired placental blood flow and suboptimal fetal nutrition may also contribute to intrauterine growth retardation and aggravated cardiovascular risk in the offspring. On the other hand, maternal overnutrition, which often contributes to obesity and/or diabetes, may result in macrosomia and enhanced cardiometabolic risk in the offspring. Progeny of obese and/or diabetic mothers are relatively more prone to develop obesity, insulin resistance, diabetes, and hypertension. It was demonstrated that they may have permanently enhanced appetites. Their atheromatous lesions are usually more pronounced. It seems that, particularly, a maternal high-fat/junk food diet may be detrimental for vascular health in the offspring. Fetal exposure to excessive levels of saturated fatty and/or n-6 fatty acids, sucrose, fructose and salt, as well as a maternal high glycemic index diet, may also contribute to later enhanced cardiometabolic risk.

Innate immunity, decidual cells, and preeclampsia

Preeclampsia (PE) manifested by hypertension and proteinuria complicates 3% to 8% of pregnancies and is a leading cause of fetal-maternal morbidity and mortality worldwide. It may lead to intrauterine growth restriction, preterm delivery, and long-term sequelae in women and fetuses, and consequently cause socioeconomic burden to the affected families and society as a whole. Balanced immune responses are required for the maintenance of successful pregnancy. Although not a focus of most studies, decidual cells, the major resident cell type at the fetal-maternal interface, have been shown to modulate the local immune balance by interacting with other cell types, such as bone marrow derived-immune cells, endothelial cells, and invading extravillous trophoblasts. Accumulating evidence suggests that an imbalanced innate immunity, facilitated by decidual cells, plays an important role in the pathogenesis of PE. Thus, this review will discuss the role of innate immunity and the potential contribution of decidual cells in the pathogenesis of PE.

Flow-mediated vasodilation is impaired in adult rat offspring exposed to prenatal hypoxia

There is now a demonstrated association between low birth weight and increased mortality later in life. Changes in fetal development may program the cardiovascular system and lead to an increased risk of cardiovascular diseases later in life. In addition, aging is a risk factor for vascular endothelial-dependent dysfunction. However, the impact of being born intrauterine growth restricted (IUGR) on the normal aging mechanisms of vascular dysfunction is not clear. We hypothesized that IUGR would cause changes in vascular function that would affect the mechanisms of flow-induced vasodilation later in life in an age- or sex-dependent manner. To create an IUGR model, pregnant Sprague-Dawley rats were placed in a hypoxic (11.5% O2) or control (room air, 21% O2) environment from days 15 to 21 of pregnancy. Both male and female offspring were investigated at 4 or 12 mo of age. Vascular function was assessed in small mesenteric arteries using flow-induced vasodilation, a physiological stimuli of vasodilation, in a pressure myograph. Flow-induced vasodilation was unaffected at a young age, but was significantly reduced in aging IUGR compared with aging controls ( P < 0.05). Underlying vasodilator mechanisms were altered such that nitric oxide-mediated vasodilation was abolished in both young adult and aging IUGR males and females and in aging control females ( P > 0.05). Endothelium-derived hyperpolarizing factor-mediated vasodilation was maintained in all groups ( P < 0.01). A change in the mechanisms of vasodilation occurring at an earlier age in IUGR offspring may predispose them to develop cardiovascular diseases as an aging adult.

The effect of feto-maternal size and childhood growth on left ventricular mass and arterial stiffness in Afro-Caribbean children

We hypothesized that maternal size, fetal size and childhood growth are associated with childhood blood pressure, left ventricular mass (LVM) and arterial stiffness. The Vulnerable Windows Cohort is a longitudinal study of 569 mothers and their offspring. Anthropometry was measured on each child at birth, at 6 weeks, once in 3 months upto 2 years and then every 6 months. Blood pressure and body composition were assessed in 185 children (age 11.5 years) and echocardiography performed. LVM was not associated with maternal size after adjustment for child's weight. LVM was significantly associated with faster growth in childhood and with current weight, fat mass and lean mass. Systolic blood pressure was not related to maternal, fetal or newborn anthropometry, but was positively associated with infant and childhood growth, as well as current body size and fat mass. The pulse pressure/stroke volume ratio (an index of arterial stiffness) was inversely associated with maternal size, placental volume at 20 weeks, fetal size at 35 weeks and childhood growth even after adjustment for current weight. In conclusion, LVM in childhood is positively associated with maternal height, child's current size and rate of growth. Arterial stiffness is inversely related to maternal, fetal and placental size as well as growth throughout childhood.