Aortic intima-media thickness measured by trans-abdominal ultrasound as an early life marker of subclinical atherosclerosis

Assessment of Vascular Indices by Abdominal Aortic Ultrasonography in Preterm Neonates with Bronchopulmonary Dysplasia

Preterm infants with bronchopulmonary dysplasia (BPD) frequently encounter systemic hypertension, yet the underlying cause remains elusive. Given the absence of prior investigations concerning the correlation between systemic hypertension and aortic thickness, we undertook this study to assess and juxtapose diverse vascular indices amidst preterm neonates with BPD, preterm neonates lacking BPD, and healthy neonates, utilizing abdominal aorta ultrasonography. This cross-sectional study encompassed 20 preterm neonates, 20 preterm neonates with BPD, and 20 healthy neonates, meticulously matched for sex and postnatal age. Comprehensive demographic, anthropometric, and clinical evaluation data were documented. The neonates underwent abdominal aortic ultrasonography for comparative evaluation of aortic wall thickness and vasomotor function across the three groups. The study revealed that neonates with BPD exhibited a notably higher average systolic blood pressure than preterm and term neonates (P < 0.05). Conversely, echocardiographic parameters such as input impedance, and arterial wall stiffness index displayed no substantial variance among the three groups (P > 0.05). The mean (SD) aortic intima-media thickness (aIMT) for preterm neonates with BPD, preterm neonates, and term neonates were 814 (193.59) μm, 497.50 (172.19) μm, and 574.00 (113.20) μm, correspondingly (P < 0.05). Furthermore, the mean (SD) pulsatile diameter for preterm neonates with BPD, preterm neonates, and term neonates were 1.52 (0.81) mm, 0.91 (0.55) mm, and 1.34 (0.51) mm, respectively (P < 0.05). Following adjustment for birth weight, sex, and gestational age at birth, the study identified a noteworthy correlation between aIMT and BPD. The investigation concluded that the mean aortic intima-media thickness (aIMT) was significantly elevated in preterm neonates with BPD, signifying a potential early indicator of atherosclerosis and predisposition to future heightened blood pressure and cardiovascular ailments. Consequently, the study postulates that aIMT could be a consistent and well-tolerated marker for identifying BPD patients at risk of developing these health complications.

Moderate-Intensity Exercise Improves Mesenteric Arterial Function in Male UC Davis Type-2 Diabetes Mellitus (UCD-T2DM) Rats: A Shift in the Relative Importance of Endothelium-Derived Relaxing Factors (EDRF)

The beneficial cardiovascular effects of exercise are well documented, however the mechanisms by which exercise improves vascular function in diabetes are not fully understood. This study investigates whether there are (1) improvements in blood pressure and endothelium-dependent vasorelaxation (EDV) and (2) alterations in the relative contribution of endothelium-derived relaxing factors (EDRF) in modulating mesenteric arterial reactivity in male UC Davis type-2 diabetes mellitus (UCD-T2DM) rats, following an 8-week moderate-intensity exercise (MIE) intervention. EDV to acetylcholine (ACh) was measured before and after exposure to pharmacological inhibitors. Contractile responses to phenylephrine and myogenic tone were determined. The arterial expressions of endothelial nitric oxide (NO) synthase (eNOS), cyclooxygenase (COX), and calcium-activated potassium channel (K_Ca) channels were also measured. T2DM significantly impaired EDV, increased contractile responses and myogenic tone. The impairment of EDV was accompanied by elevated NO and COX importance, whereas the contribution of prostanoid- and NO-independent (endothelium-derived hyperpolarization, EDH) relaxation was not apparent compared to controls. MIE 1) enhanced EDV, while it reduced contractile responses, myogenic tone and systolic blood pressure (SBP), and 2) caused a shift away from a reliance on COX toward a greater reliance on EDH in diabetic arteries. We provide the first evidence of the beneficial effects of MIE via the altered importance of EDRF in mesenteric arterial relaxation in male UCD-T2DM rats.

Early Life Determinants of Vascular Structure in Fetuses, Infants, Children, and Adolescents: A Systematic Review and Meta-Analysis

OBJECTIVE

To investigate the association between early life exposures during the first 1000 days (conception to age 24 months) and aortic intima-media thickness (aIMT), an early indicator of cardiovascular disease (CVD) risk, in youths.

STUDY DESIGN

The MEDLINE, Embase, Scopus, CINAHL, and Allied and Complementary Medicine databases were searched from inception to July 2021. Eligibility criteria included observational controlled studies in youths aged <20 years with risk factors/exposures during the first 1000 days and aIMT measurements (unadjusted mean ± SD). Outcome data were pooled using a random-effects meta-analysis. Meta-regression was used to investigate confounders.

RESULTS

A total of 8657 articles were identified, of which 34 were included in our meta-analysis. The age of participants ranged from 22.9 weeks gestation in utero to 10.9 years. In the meta-analysis (n = 1220 cases, n = 1997 controls), the following factors were associated with greater aIMT: small for gestational age (SGA) status (14 studies, mean difference, 0.082 mm; 95% CI, 0.051-0.112; P < .001; I² = 97%), intrauterine growth restriction (6 studies; mean difference, 0.198 mm, 95% CI, 0.088-0.309; P < .001; I² = 97%), preeclampsia (2 studies; mean difference, 0.038 mm; 95% CI, 0.024-0.051; P < .001; I² = 38%), and large for gestational age (LGA) status (3 studies; mean difference, 0.089 mm; 95% CI, 0.043-0.0136; P < .001; I² = 93%). In meta-regression, older age (P < .001), higher prevalence of maternal smoking (P = .04), and SGA (P < .001) were associated with greater difference in aIMT in preterm participants compared with controls. Limitations included the high heterogeneity present in most meta-analyses and the scope of our meta-regression.

CONCLUSIONS

Adverse early life exposures are associated with greater aIMT in youths, consistent with an increased risk for CVD later in life. Further research is needed to determine whether intervention and preventive strategies deliver clinical benefits to improve future cardiovascular health.

Aortic Intima-Media Thickness is Increased in Neonates of Mothers with Gestational Diabetes Mellitus: The Role of Thioredoxin-Interacting Protein as a Marker of Oxidative Stress

BACKGROUND

Offspring exposed in foetal life to gestational diabetes mellitus (GDM) are at increased risk for future metabolic diseases.

OBJECTIVE

To explore the prognostic role of abdominal aorta intima-media thickness (aIMT) in neonates exposed to GDM as a possible biomarker for later atherogenesis and its possible correlation with thioredoxin- interacting protein (TXNIP), a protein involved in oxidative stress.

METHODS

In this prospective, observational study, mother-infant pairs were studied in 2 groups (57 patients with GDM and 51 controls without GDM). TXNIP levels were measured in the placenta, as well as in the umbilical and neonatal blood. The data were correlated with aIMT in neonates.

RESULTS

aIMT was increased in GDM offspring (patients: median [range]=0.39 mm [0.31-0.46] vs controls: median=0.28 mm [0.23-0.33]; p=0.001) and remained significant after adjusting for possible confounders (e.g., triglycerides, blood pressure, vitamin D, birth weight and gender; β coefficient=0.131 p=0.049). TXNIP levels were increased in trophoblasts (p=0.001) and syncytiotrophoblasts (p=0.001) and were decreased in endothelial cells (p=0.022) in GDM offspring vs controls. Moreover, TXNIP levels in trophoblasts positively correlated with aIMT (r=0.369; p=0.001). TXNIP levels in umbilical/ neonatal blood were not associated with GDM.

CONCLUSION

Increased aIMT was demonstrated in the offspring of mothers with GDM. Non-invasive measurement of aIMT could be used as a biomarker to identify children at increased risk for atherogenesis later in life. This information may encourage early preventive measures. TXNIP may be associated with GDM and/or aIMT.

Sonographic Cardiovascular Assessment of the Aorta: Pilot of a Modified Image Grading System

Objective:

Atherosclerosis is a chronic inflammatory disease that can be undetected in middle-aged patients. Abdominal aortic calcifications (AACs) are one form of cardiovascular disease (CVD), and these can go undetected during a routine physician visit. Sonography has the potential to assess CVD progression, quantify plaque in the aorta, and help to quantify risk in asymptomatic patients.

Methodology:

This pilot study modified a current AAC grading system to create a scoring method for sonographic images among a small cohort of asymptomatic participants. A traditional portable ultrasound unit was used to image participants, and a subset underwent the same imaging with a handheld transducer and tablet.

Results:

In this cohort, six males and five females, it was possible to adequately visualize and assess plaque, utilizing both types of ultrasound equipment. The abdominal aorta was divided into segments on the sonogram for quality of grading. Ten participants were categorized with a grade II and one participant was given a grade IIIA.

Conclusion:

Replication of this modified grading system is needed to better understand the clinical utilization of sonography as a risk assessment tool. The risk assessment scoring was not dependent on the type of device used.

Regional functional and structural abnormalities within the aorta as a potential driver of vascular disease in metabolic syndrome

NEW FINDINGS

What is the central question of this study? Is aortic dysfunction, a significant contributor to cardiovascular disease in metabolic syndrome, expressed uniformly across both the thoracic and abdominal aorta? What is the main finding and its importance? Our study shows that, in the setting of metabolic syndrome, functional and structural deficits in the aorta are differentially expressed along its length, with the abdominal portion displaying more extensive vascular abnormalities. It is, therefore, likely that early interventional strategies targeting the abdominal aorta might alleviate cardiovascular pathologies driven by the metabolic syndrome.

ABSTRACT

The extent of vascular dysfunction associated with metabolic syndrome might vary along the length of the aorta. In this study, we investigated regional functional and structural changes in the thoracic and abdominal aorta of a rat model of metabolic syndrome, namely, high-fat diet (HFD) streptozotocin-induced diabetes mellitus (HFD-D). Four-week-old male Wistar albino rats were fed with either HFD or control diet (CD) for 10 weeks. At week 6, 40 mg/kg streptozotocin and its vehicle were injected i.p. into HFD and CD groups, respectively. At the end of the feeding period, rats were euthanised and aortic segments collected for assessment of vascular functional responses and histomorphometry. Tail-cuff systolic blood pressures (154 ± 6  vs. 110 ± 4 mmHg) and areas under the curve for oral glucose and i.p. insulin tolerance tests were greater in HFD-D versus CD rats. Abdominal aortic vasoconstriction in response to noradrenaline and KCl was greater in HFD-D compared with CD rats. Thoracic vasoconstrictor responses to noradrenaline, but not KCl, were greater in the HFD-D group. Abdominal, but not thoracic, endothelium-dependent vasorelaxation in response to acetylcholine was blunted in HFD-D relative to CD rats; however, nitric oxide-dependent vasorelaxation in HFD-D rats was impaired in both thoracic and abdominal segments. The abdominal aorta of HFD-D rats showed deranged interlamellar spacing and increased lipid plaque deposition. In conclusion, vascular dysfunction in metabolic syndrome is expressed differentially along the length of the aorta, with the abdominal aorta exhibiting increased susceptibility to vasoconstrictors and greater deficits in endothelium-dependent relaxation. These vascular functional abnormalities could potentially underlie the development of hypertensive cardiovascular disease associated with the metabolic syndrome.

Vitamin D and its correlation with blood lipids and intima-media thickness in term infants

Introduction

Background: an association between low 25(OH)D levels and blood lipids has been identified in children, adolescents, and adults but not in the early stages of life, and a relation to carotid and aortic intima-media thickness has not been well studied and is controversial. Objective: to identify whether 25(OH)D levels are correlated with blood lipids and aortic and carotid intima-media thickness in infants aged 3 to 9 months. Methods: a cross-sectional study was conducted in 109 healthy term infants between the ages of 3 and 9 months. Serum vitamin D [25(OH)D], total cholesterol, HDL-cholesterol, non-HDL-cholesterol, and aortic and carotid intima-media thickness were measured. Feeding method, vitamin D supplementation, and sun exposure habits were recorded. Results: only 2.8 % (n = 3) and 10.1 % (n = 14) had vitamin D deficiency and insufficiency, respectively. Infants with inadequate levels of vitamin D were younger (< 6 months) (p = 0.004), and a lower percentage of their body surface area was exposed to the sun (p = 0.006). A significant positive correlation was found between 25(OH)D levels and non-HDL-cholesterol in the infants that consumed breastmilk substitutes (rho = 0.600, p < 0.001) or were partially breastfed (rho = 0.371, p = 0.026), whereas a positive correlation was found with total cholesterol in the infants receiving breastmilk substitutes (rho = 0.618, p < 0.001). No significant correlation was found between vitamin D and aortic or carotid intima-media thickness. Conclusions: there was a positive correlation between 25(OH)D levels and both total and non-HDL-cholesterol only in infants receiving breastmilk substitutes. The frequency of vitamin D deficiency and insufficiency was low.

Aortic intima-media thickness in neonates exposed to early-onset preeclampsia

Aortic intima-media thickness (aIMT) and its ratio to aortic diameter (aIMT/AoD) were measured on the second and fifth postnatal day in 39 neonates exposed to early-onset preeclampsia and 39 controls. Both aIMT and aIMT/AoD were higher in neonates exposed to preeclampsia (P < 0.001 for all comparisons).

HIF3A cord blood methylation and systolic blood pressure at 4 years - a population-based cohort study

Methylation levels at the hypoxia-inducible factor 3α gene (HIF3A) in blood have been linked to body mass index (BMI) in adults. Despite evidence implicating HIF3A in angiogenesis and metabolism, no studies have examined links between HIF3A methylation in early life and cardiovascular health. Here, we investigated the relationship between HIF3A methylation in blood at birth and 12 months of age with cardiovascular measures at 4 years. We also examined influences of prenatal exposures, birth outcomes, and genetic variation. Methylation of two HIF3A promoter regions in cord blood was measured using Sequenom EpiTYPER mass-spectrometry. The first promoter region was also measured in 12-month blood. Four-year cardiovascular measures included blood pressure, pulse wave velocity, and aortic and carotid intima-media thickness. Associations were tested using partial correlation tests and linear regression modelling. Methylation of the first HIF3A promoter in cord and 12-month blood was not associated with four-year measures. There was modest evidence of an association between DNA methylation at the second HIF3A promoter in cord blood and four-year systolic blood pressure (n = 353, r = 0.12, p = 0.03). In sex-stratified analysis, methylation of the second promoter was modestly associated with systolic and diastolic blood pressure (r = 0.16, p = 0.03 for both) in males only. In conclusion, HIF3A methylation at birth shows some evidence of an association with later blood pressure in childhood. Further work should determine whether this relationship persists into later childhood, and should assess potential functional links between HIF3A methylation and cardiovascular health more generally.

Carotid intima-media thickness values are significantly higher in patients with prediabetes compared to normal glucose metabolism

Carotid intima-media thickness (C-IMT) increases in patients with adult type-2 diabetes mellitus (DM) and is used for early detection of macrovascular complications. We aimed to investigate the change of C-IMT in prediabetes and type-2 DM patients compared to subjects with normal glucose metabolism (NGM).A total of 180 individuals (60 subjects with NGM, 60 patients with prediabetes and 60 patients with type-2 DM) were included in this study. Routine laboratory and micro-macrovascular involvement were investigated. Urine albumin-creatinine ratio (ACR) was measured for urinary albuminuria detection. In addition to routine laboratory examination, right-left common and internal C-IMT (CC-IMT and IC-IMT) were measured.Systolic and diastolic blood pressure values were found to be higher in prediabetes and type-2 DM groups than NGM group. The prevalence of nephropathy and presence of CAD were higher in type-2 DM groups than prediabetes. Glucose, glycated hemoglobin (HbA1c), total cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, blood urea nitrogen, creatinine, high sensitive C reactive protein (hs-CRP) levels and urinary ACR were significantly higher in patients within prediabetes and type-2 DM groups than NGM group. Glucose, HbA1c and hs-CRP levels were found to be higher in type-2 DM groups than prediabetes. Estimated glomerular filtration rate and high-density lipoprotein (HDL) cholesterol level was found to be lower in patients within prediabetes and type-2 DM groups than NGM group. Right-left-mean CC-IMT and IC-IMT values were found to be higher in prediabetes and type-2 DM groups than NGM group. Left IC-IMT, left CC-IMT, and mean IC-IMT values were found to be higher in type-2 DM patients compared to prediabetes. LDL and HDL cholesterols, HbA1c, and hs-CRP levels were independently associated with IC-IMT and CC-IMT.C-IMT values were significantly higher in impaired glucose metabolism compared to NGM. C-IMT measurement may be used as part of routine screening of macrovascular complication in patients with prediabetes and newly diagnosed type-2 DM.

Aortic intima-media thickness can be used to determine target organ damage in adult patients with coronary artery disease risk factors

Introduction

We aimed to evaluate the relationship between abdominal aortic intima-media thickness (AA-IMT) and thoracic aortic intima-media thickness (TA-IMT) values and to investigate their relationship with common carotid intima-media thickness (CC-IMT) in patients with coronary artery disease (CAD) risk factors.

Material and methods

This study included 100 patients who underwent transesophageal echocardiography (TEE) examination for different reasons with at least one CAD risk factor. CC-IMT, AA-IMT, and TA-IMT values were measured. Patients with CC-IMT > 0.9 mm were considered as having increased CC-IMT. Patients were divided into two groups with and without increased CC-IMT.

Results

Mean AA-IMT and TA-IMT values of all patients were 1.55 ±0.27 mm and 1.39 ±0.25 mm, respectively. In patients with increased CC-IMT, blood pressure, hyperlipidemia and hypertension frequency, creatinine, total and low-density lipoprotein (LDL) cholesterol, triglyceride, high-sensitivity C-reactive protein (hs-CRP) and uric acid levels, AA-IMT and TA-IMT values were higher, while the high-density lipoprotein (HDL) cholesterol level was lower than the normal CC-IMT group. AA-IMT, systolic blood pressure (SBP), total and HDL cholesterol levels independently determined the patients with CC-IMT > 0.9 mm. Each 0.1 mm increase in AA-IMT value was found to increase the probability of having CC-IMT > 0.9 mm. In addition, linear regression analysis showed that CC-IMT was closely and independently related to AA-IMT (p < 0.001 and β = 0.599). When the cut-off value for AA-IMT was taken as 1.5 mm, it determined the patients with CC-IMT > 0.9 mm with 86% sensitivity and 82% specificity.

Conclusions

The AA-IMT value was found to be higher than TA-IMT in the same patient. Also it was found that AA-IMT was more closely related to CC-IMT.

Feasibility and Normal Ranges of Arterial Intima-Media Thickness and Stiffness in 2-Year-Old Children: A Pilot Study

INTRODUCTION

In adults, noninvasive assessments of vascular function have been established. However, little is known about the applicability and reference values of these techniques among children < 6 years old and none ≤ 2. We aimed to determine the feasibility of conducting noninvasive vascular assessments in 2-year-old children and the normal range of results in this age group.

METHODS

Carotid intima-media thickness (cIMT) and abdominal aorta IMT (aaIMT), pulse wave velocity (PWV), arterial diameter change, stiffness index (β), and distensibility were assessed in 2-year-old children. IMT was assessed using an automatic contour detection.

RESULTS

The proportion of successful measurements was 72% (42/58) with cIMT 64%, aaIMT 67%, and PWV 43%. Average far wall cIMT was 0.51 mm and 0.40 for aaIMT. Mean PWV was 4.15 m/s, with relatively wider range in stiffness index and distensibility. Common carotid arteries had a higher mean distensibility of 4.58%/10 mmHg compared with 2.98%/10 mmHg for the abdominal aorta. The number of data points automatically detected at far wall cIMT was higher than that in aaIMT (left cIMT: 244 ± 13 and right: 240 ± 23 vs. abdominal 185 ± 63, p < 0.001). Better and more consistent quality was achieved for cIMT than aaIMT measurements. PWV measurement was only feasible in cooperative children with efficient distractions.

CONCLUSIONS

Noninvasive methods for early detection of cardiovascular risks were feasible in at least two-thirds of 2-year-old children. Given the greater feasibility and image quality, cIMT is a preferable option for assessing vascular health in young children.

The sequence of prenatal growth restraint and postnatal catch-up growth: normal heart but thicker intima-media and more pre-peritoneal fat in late infancy

BACKGROUND

The sequence of prenatal growth restraint and postnatal catch-up growth leads to a thicker intima-media and more pre-peritoneal fat by age 3-6 years.

OBJECTIVES

To study whether carotid intima-media thickness (cIMT) and pre-peritoneal fat differ already between catch-up small-for-gestational-age (SGA) infants and appropriate-for-gestational-age (AGA) controls in late infancy (ages 1 and 2 years) and whether such differences - if any - are accompanied by differences in cardiac morphology and function.

METHODS

Longitudinal assessments included body height and weight; fasting glucose, insulin, Insulin-like growth factor (IGF-I), high-molecular-weight adiponectin; body composition (by absorptiometry); cIMT, aortic IMT, pre-peritoneal fat partitioning (by ultrasound); cardiac morphometry and function (by echocardiography) in AGA and SGA infants at birth, at age 1 year (N = 87), and again at age 2 years (N = 68).

RESULTS

Catch-up SGA infants had already a thicker cIMT than AGA controls at ages 1 and 2 years, and more pre-peritoneal fat by age 2 years (all p values between <0.01 and <0.0001); all cardiac and endocrine-metabolic results were similar in AGA and SGA infants at ages 1 and 2 years.

CONCLUSIONS

From late infancy onwards, catch-up SGA infants have a thicker cIMT and more pre-peritoneal fat than AGA controls, but their cardiac morphology and function remain reassuringly similar.

Increased aortic intima-media thickness may be used to detect macrovascular complications in adult type II diabetes mellitus patients

Background

Carotid intima media thickness (C-IMT) and aortic IMT (A-IMT) increase in adult and pediatric patients with diabetes mellitus (DM), respectively. In both age groups IMT is used for early detection of macrovascular complications. In adult DM patients, A-IMT is still not a routine examination and is not used frequently. We aimed to determine whether there is an increase in A-IMT values measured from abdominal aorta besides traditional C-IMT in patients with type II DM and to determine parameters closely related to A-IMT in the same patient group.

Methods

We included 114 type II DM patients and 100 healthy control subjects similar in age and sex in our study. Bilateral C-IMT and A-IMT values were measured by B-mode ultrasonography (USG) in addition to anamnesis, physical examination and routine examinations of all patients.

Results

When the clinical, demographic and laboratory data of patients with and without DM were compared, there was a high level of glucose and HbA1c and low hemoglobin levels in the DM patient group. All other parameters were found to be similar between the two groups. When the B-mode USG findings were examined, it was found that C-IMT and A-IMT were increased in patients with DM, with the A-IMT increase being more prominent. A-IMT values were found to be strongly and positively correlated with age, systolic blood pressure, blood urea nitrogen, DM onset time and HbA1c levels, and a negatively and significantly correlated with hemoglobin levels (p < 0.05, for each). In the regression model, the parameters correlating most closely with A-IMT were DM diagnosis onset time, HbA1c and hemoglobin levels (p = 0.001 and β = 0.353, p = 0.014 and β = 0.247 and p < 0.001 and β = − 0.406).

Conclusions

As in pediatric DM patients also in adult DM patients A-IMT can easily be measured with new model USG devices. A-IMT must be measured during abdominal USG which is routine in adult DM patients. A-IMT is an easy, reproducible and non-invasive parameter that may be used in the diagnosis of macrovascular complications of adult type II DM.

Intima-media thickness at different arterial segments in pediatric type 1 diabetes patients and its relationship with advanced glycation end products

BACKGROUND

Patients with type 1 diabetes mellitus (T1DM) are at risk for premature atherosclerosis (AS), which has its origin in childhood. Carotid intima-media thickness (IMT) is an established surrogate marker for subclinical AS in adults. The first macroscopically detectable AS changes, however, begin in the abdominal aorta. Advanced glycation end products (AGE) predict microvascular complications in diabetes.

OBJECTIVES

To assess the sensitivity for early macrovascular changes of brachial, femoral, and aortic IMT compared to conventional carotid IMT in pediatric T1DM patients ; and the relationship of IMT with AGE.

METHODS

Using high-resolution external ultrasound, carotid, brachial, femoral, and aortic IMT were prospectively analyzed in children and adolescents with established T1DM and in controls (Ctrls). AGE were estimated by skin intrinsic fluorescence (SIF). Other established cardiovascular risk factors were excluded.

RESULTS

Seventy-six subjects (T1DM = 38; Ctrls = 38) with a mean age of 13.1 ± 4.0 years (6-19, median 13) qualified for analysis. Carotid, brachial, femoral, and aortic IMT analyses were feasible in 100%, 74%, 84%, and 92% of subjects, respectively. Aortic and femoral IMT were increased in T1DM patients (0.60 ± 0.11 vs 0.52 ± 0.10 mm, P < .001; and 0.41 ± 0.07 vs 0.36 ± 0.07 mm, P < .01, respectively) while carotid and brachial IMT were not. AGE levels were elevated in T1DM patients and correlated with aortic IMT only. The influence of AGE on aIMT did not remain significant after adjusting for T1DM and age in our small population.

CONCLUSION

We found aortic IMT-and to a lesser degree femoral IMT-to be more sensitive than carotid and brachial IMT for detecting early macrovascular changes in pediatric T1DM patients.

Perinatal microbial exposure may influence aortic intima-media thickness in early infancy

Background

The maternal and infant microbiome may influence infant cardiovascular risk through immune programming. The maternal vagino-enteric microbiome is often sampled for group B streptococcus (GBS) colonization during pregnancy. Our aim was to investigate the association between maternal GBS colonization, intrapartum antibiotics, antenatal pet exposure and infant aortic intima-media thickness (aIMT), an intermediate vascular phenotype, and whether this association varied by mode of delivery.

Methods

The Barwon Infant Study is a population-derived pre-birth cohort. Perinatal data were collected on participants. Women were tested for vagino-enteric group B streptococcus (GBS) colonization during third trimester. Six-week infant aIMT was measured by trans-abdominal ultrasound. Adjustment for confounders included maternal age, pre-pregnancy body mass index (BMI), smoking, socioeconomic status, gestational diabetes, length of gestation, infant sex, birthweight and aortic internal diameter.

Results

Data were available on 835 mother-infant pairs. Of these, 574 (69%) women delivered vaginally; of those, 129 (22%) were GBS-colonized; and of these women, 111 (86%) received prophylactic intrapartum antibiotics. An association between maternal GBS colonization and infant aIMT was observed among those delivered vaginally (β = 19.5 µm, 95% CI 9.5, 29.4; P  < 0.0001) but not by Caesarean section ( P for interaction = 0.02). A similar pattern was seen for intrapartum antibiotics. There was a negative association between antenatal pet exposure and aIMT observed in those delivered vaginally.

Conclusion

Maternal GBS colonization and intrapartum antibiotics were associated with increased infant aIMT in those delivered vaginally, whereas antenatal pet exposure was associated with decreased aIMT. These data suggest that differences in early life microbial experience may contribute to an increased cardiovascular risk.

Early-Life Markers of Atherosclerosis Using Aortic and Carotid Intima-Media Thickness: An Assessment of Methods to Account for Child Size

Background

Distinguishing pathological from physiological relationships between vessel size and aortic intima-media thickness (aIMT) is an important challenge, especially in growing children. We examined the relationship between childhood vessel diameter and aIMT and assessed common analytic approaches used to address this relationship.

Methods

We analyzed aIMT in two population-derived cohorts; 6-week-old infants and 19-year-olds. We simulated datasets in which we assumed a simple physiological relationship between vessel diameter and aIMT, and then superimposed possible pathological effects on aIMT; (a) intrauterine growth retardation, (b) macrosomia and (c) both intrauterine growth retardation and macrosomia. Using simulated datasets and cohorts, we evaluated analytic strategies including those in which the relationship between vessel diameter and aIMT was (a) ignored, (b) adjusted for by dividing aIMT by weight, or (c) adjusted for using varying regression techniques.

Results

aIMT was found to increase in proportion to vessel diameter in both cohorts (138 μm/mm at 6 weeks and 52 μm/mm at 19 years of age). Simply dividing aIMT by weight produced negative associations with weight across all datasets. By contrast, adjusting for vessel diameter as a covariate enabled accurate distinction of the direction of the association between aIMT and weight in all simulated datasets. These results were replicated in the cohort studies for both aIMT and carotid intima-media thickness.

Conclusion

There is a physiological relationship between vessel diameter and aIMT. Simply dividing aIMT by weight may lead to incorrect assumptions regarding the relationship between weight and aIMT. However, the physiological relationship is appropriately estimated by including vessel diameter as a covariate in regression.

Methods to evaluate arterial structure and function in children - State-of-the art knowledge

BACKGROUND

With increasing rates of hypertension, obesity, and diabetes in the pediatric population, wide available, and reproducible methods are necessary to evaluate arterial structure and function in children and adolescents.

METHODS

MEDLINE/Pubmed was searched for articles published in years 2012-2017 on methodology of, current knowledge on, and limitations of the most commonly used methods to evaluate central, proximal and coronary arteries, as well as endothelial function in pediatric patients.

RESULTS

Among 1528 records screened (including 1475 records from years 2012 to 2017) 139 papers were found suitable for the review. Following methods were discussed in this review article: ultrasound measurements of the intima-media thickness, coronary calcium scoring using computed tomography, arterial stiffness measurements (pulse wave velocity and pulse wave analysis, carotid artery distensibility, pulse pressure, and ambulatory arterial stiffness index), ankle-brachial index, and methods to evaluate vascular endothelial function (flow-mediated vasodilation, peripheral arterial tonometry, Doppler laser flowmetry, and cellular and soluble markers of endothelial dysfunction).

CONCLUSIONS

Ultrasonographic measurement of carotid intima-media thickness and measurement of pulse wave velocity (by oscillometry or applanation tonometry) are highly reproducible methods applicable for both research and clinical practice with proved applicability for children aged ≥6 years or with height ≥120cm. Evaluation of ambulatory arterial stiffness index by ambulatory blood pressure monitoring is another promising option in pediatric high-risk patients. Clearly, further studies are necessary to evaluate usefulness of these and other methods for the detection of subclinical arterial damage in children.

The sequence of prenatal growth restraint and post-natal catch-up growth leads to a thicker intima-media and more pre-peritoneal and hepatic fat by age 3-6 years

BACKGROUND

Infants born small-for-gestational-age (SGA) who develop post-natal weight catch-up are at risk for insulin resistance, central adiposity and cardiovascular disease in later life, even in the absence of overweight.

OBJECTIVE

In young (age 3-6 years) non-obese SGA children, we assessed arterial health (as judged by intima-media thickness [IMT]) and abdominal fat distribution (subcutaneous, visceral, preperitoneal and hepatic components by magnetic resonance imaging [MRI] and/or ultrasound [US]) besides a selection of endocrine markers.

METHODS

Comparisons of measures in SGA (n = 27) vs. appropriate-for-GA (AGA) children (n = 19) of similar height, weight and body mass index. Longitudinal outcomes (age 3-6 years) were carotid IMT (cIMT); fasting glucose, circulating insulin, IGF-I and high-molecular-weight (HMW) adiponectin; abdominal fat partitioning by US. Cross-sectional outcomes (age 6 years) were aortic IMT (aIMT) and abdominal fat partitioning by MRI.

RESULTS

At 3 and 6 years, cIMT and IGF-I results were higher and HMW adiponectin lower in SGA than AGA children; at 6 years, SGA subjects had also a thicker aIMT and more pre-peritoneal and hepatic fat, and were less insulin sensitive (all P values between <0.05 and <0.0001). cIMT correlated positively with pre-peritoneal fat, particularly at 6 years. Post-SGA status and weight gain in early childhood (between 3 and 6 years) were independent predictors of cIMT at 6 years, explaining 48 % of its variance.

CONCLUSION

SGA children aged 3-6 years were found to have a thicker intima- media and more pre-peritoneal and hepatic fat than AGA children of comparable size.

Infant adiposity at birth and early postnatal weight gain predict increased aortic intima-media thickness at 6 weeks of age: a population-derived cohort study

Infant body composition and postnatal weight gain have been implicated in the development of adult obesity and cardiovascular disease, but there are limited prospective data regarding the association between infant adiposity, postnatal growth and early cardiovascular parameters. Increased aortic intima-media thickness (aortic IMT) is an intermediate phenotype of early atherosclerosis. The aim of the present study was to investigate the relationship between weight and adiposity at birth, postnatal growth and aortic IMT. The Barwon Infant Study (n=1074 mother-infant pairs) is a population-derived birth cohort. Infant weight and other anthropometry were measured at birth and 6 weeks of age. Aortic IMT was measured by trans-abdominal ultrasound at 6 weeks of age (n=835). After adjustment for aortic size and other factors, markers of adiposity including increased birth weight (β=19.9 μm/kg, 95%CI 11.1, 28.6; P<0.001) and birth skinfold thickness (β=6.9 μm/mm, 95%CI 3.3, 10.5; P<0.001) were associated with aortic IMT at 6 weeks. The association between birth skinfold thickness and aortic IMT was independent of birth weight. In addition, greater postnatal weight gain was associated with increased aortic IMT, independent of birth weight and age at time of scan (β=11.3 μm/kg increase, 95%CI 2.2, 20.3; P=0.01). Increased infant weight and adiposity at birth, as well as increased early weight gain, were positively associated with aortic IMT. Excessive accumulation of adiposity during gestation and early infancy may have adverse effects on cardiovascular risk.

Feasibility and precision of transcutaneous very-high resolution ultrasound for quantification of arterial structures in human neonates - comparison with conventional high resolution vascular ultrasound imaging

BACKGROUND

Non-invasive transcutaneous very-high resolution ultrasound (VHRU, 25-55 MHz) has recently been developed to quantify superficial vascular structures in humans. The performance of the method has yet not been evaluated in vivo in neonates. The aim of the study was to compare VHRU with conventional high-resolution ultrasound (HRU, 7-12 MHz), and to assess the feasibility and precision of VHRU in this population.

METHODS

150 images from central elastic (common carotid, CCA) and peripheral muscular (brachial, BA; femoral, FA) arteries were obtained in 25 neonates of different gestational ages (range 33 + 0 to 41 + 5 gestational weeks) and weights (range 1570-4950 g) with VHRU, and the use of HRU for comparison assessed in five.

RESULTS

Images were captured from CCAs with 35 MHz, FAs using 35 and 55 MHz, and BAs using 55 MHz. 12 MHz was unable to assess FAs and BAs, and the CCA IMT was grossly overestimated compared with 35-55 MHz. IMTs of the smallest BAs and FAs were beyond the axial resolution of VHRU (<0.05 mm), thus immeasurable. For VHRU, the intra-, inter- and test-retest coefficients of variation (CV) were for LDs (range 1.44-2.62 mm, CVs between 1.6 and 4.8%), IMATs (range 0.141-0.161 mm, CVs between 8.8 and 19.9%), and IMTs (range 0.062-0.165 mm, CVs between 12.8 and 24.8%) for the different arteries.

CONCLUSION

VHRU is feasible, accurate and precise in the assessment of superficial proximal conduit arteries but unable to assess the abdominal aorta in human neonates HRU-derived neonatal conduit arterial wall layer thicknesses are below the ultrasound axial resolution.

Expression of monocyte subsets and angiogenic markers in relation to carotid plaque neovascularization in patients with pre-existing coronary artery disease and carotid stenosis

AIM

To characterize blood monocyte subsets in patients with different degrees of carotid atherosclerosis and pathological carotid plaque neovascularization.

METHODS

Assessment of carotid plaque neovascularization using contrast ultrasonography and flow cytometric quantification of monocyte subsets and their receptors involved in inflammation, angiogenesis, and tissue repair was done in 40 patients with carotid stenosis ≥ 50% and CAD (CS > 50), 40 patients with carotid stenosis < 50% and documented CAD (CS < 50), 40 hypercholesterolaemic controls (HC group), and 40 normocholesterolaemic controls (NC).

RESULTS

CS > 50 and CS < 50 groups had increased counts of Mon1 ('classical' CD14++ CD16-CCR2 + cells) compared to HCs (P = 0.03, and P = 0.009). Mon3 ('non-classical' CD14 + CD16++ CCR2- cells) were only increased in CS < 50 compared with HCs (P < 0.01). Both CS>50 and CS < 50 groups showed increased expression of proinflammatory interleukin-6 receptor on Mon1 and Mon2 ('intermediate' CD14++ CD16 + CCR2+ cells); TLR4, proangiogenic Tie2 on all subsets (P < 0.01 for all). In multivariate regression analysis only high Mon1 count was a significant predictor of carotid stenosis (P = 0.04) and intima-media thickness (P = 0.02). In multivariate regression analysis only the Mon1 subset was significantly associated with severe, grade 2 neovascularization (P = 0.034).

CONCLUSION

In this pilot study classical monocytes (Mon1) represent the only monocyte subset predictive of the severity of carotid and systemic atherosclerosis, such as carotid intima-media thickness, degree of carotid stenosis, and presence of carotid intraplaque neovascularization.

Reproducibility of aortic intima-media thickness in infants using edge-detection software and manual caliper measurements

Background

Aortic intima-media thickness measured by transabdominal ultrasound (aIMT) is an intermediate phenotype of cardiovascular risk. We aimed to (1) investigate the reproducibility of aIMT in a population-derived cohort of infants; (2) establish the distribution of aIMT in early infancy; (3) compare measurement by edge-detection software to that by manual sonographic calipers; and (4) assess the effect of individual and environmental variables on image quality.

Methods

Participants were term infants recruited to a population-derived birth cohort study. Transabdominal ultrasound was performed at six weeks of age by one of two trained operators. Thirty participants had ultrasounds performed by both operators on the same day. Data were collected on environmental (infant sleeping, presence of a sibling, use of sucrose, timing during study visit) and individual (post-conception age, weight, gender) variables. Two readers assessed image quality and measured aIMT by edge-detection software and a subset by manual sonographic calipers. Measurements were repeated by the same reader and between readers to obtain intra-observer and inter-observer reliability.

Results

Aortic IMT was measured successfully using edge-detection in 814 infants, and 290 of these infants also had aIMT measured using manual sonographic calipers. The intra-reader intra-class correlation (ICC) (n = 20) was 0.90 (95% CI 0.76, 0.96), mean difference 1.5 μm (95% LOA −39, 59). The between reader ICC using edge-detection (n = 20) was 0.92 (95% CI 0.82, 0.97) mean difference 2 μm (95% LOA −45.0, 49.0) and with manual caliper measurement (n = 290) the ICC was 0.84 (95% CI 0.80, 0.87) mean difference 5 μm (95% LOA −51.8, 61.8). Edge-detection measurements were greater than those from manual sonographic calipers (mean aIMT 618 μm (50) versus mean aIMT 563 μm (49) respectively; p < 0.001, mean difference 44 μm, 95% LOA −54, 142). With the exception of infant crying (p = 0.001), no associations were observed between individual and environmental variables and image quality.

Conclusion

In a population-derived cohort of term infants, aIMT measurement has a high level of intra and inter-reader reproducibility. Measurement of aIMT using edge-detection software gives higher inter-reader ICC than manual sonographic calipers. Image quality is not substantially affected by individual and environmental factors.