Large-artery stiffness, hypertension and cardiovascular risk in older patients

Harnessing quantum light for microscopic biomechanical imaging of cells and tissues

The biomechanical properties of cells and tissues play an important role in our fundamental understanding of the structures and functions of biological systems at both the cellular and subcellular levels. Recently, Brillouin microscopy, which offers a label-free spectroscopic means of assessing viscoelastic properties in vivo, has emerged as a powerful way to interrogate those properties on a microscopic level in living tissues. However, susceptibility to photodamage and photobleaching, particularly when high-intensity laser beams are used to induce Brillouin scattering, poses a significant challenge. This article introduces a transformative approach designed to mitigate photodamage in biological and biomedical studies, enabling nondestructive, label-free assessments of mechanical properties in live biological samples. By leveraging quantum-light-enhanced stimulated Brillouin scattering (SBS) imaging contrast, the signal-to-noise ratio is significantly elevated, thereby increasing sample viability and extending interrogation times without compromising the integrity of living samples. The tangible impact of this methodology is evidenced by a notable three-fold increase in sample viability observed after subjecting the samples to three hours of continuous squeezed-light illumination, surpassing the traditional coherent light-based approaches. The quantum-enhanced SBS imaging holds promise across diverse fields, such as cancer biology and neuroscience where preserving sample vitality is of paramount significance. By mitigating concerns regarding photodamage and photobleaching associated with high-intensity lasers, this technological breakthrough expands our horizons for exploring the mechanical properties of live biological systems, paving the way for an era of research and clinical applications.

Design of experiment approach to identify the dominant geometrical feature of left coronary artery influencing atherosclerosis

Background and Objective. Coronary artery geometry heavily influences local hemodynamics, potentially leading to atherosclerosis. Consequently, the unique geometrical configuration of an individual by birth can be associated with future risk of atherosclerosis. Although current researches focus on exploring the relationship between local hemodynamics and coronary artery geometry, this study aims to identify the order of influence of the geometrical features through systematic experiments, which can reveal the dominant geometrical feature for future risk assessment.Methods. According to Taguchi's method of design of experiment (DoE), the left main stem (LMS) length (lLMS), curvature (kLMS), diameter (dLMS) and the bifurcation angle between left anterior descending (LAD) and left circumflex (LCx) artery (αLAD-LCx) of two reconstructed patient-specific left coronary arteries (LCA) were varied in three levels to create L9 orthogonal array. Computational fluid dynamic (CFD) simulations with physiological boundary conditions were performed on the resulting eighteen LCA models. Average helicity intensity (h2) and relative atheroprone area (RAA) of near-wall hemodynamic descriptors were analyzed.Results. The proximal LAD (LADproximal) was identified to be the most atheroprone region of the left coronary artery due to higherh2,large RAA of time averaged wall shear stress (TAWSS < 0.4 Pa), oscillatory shear index (OSI ∼ 0.5) and relative residence time (RRT > 4.17 Pa-1). In both patient-specific cases, based onh2and TAWSS,dlmsis the dominant geometric parameter while based on OSI and RRT,αLAD-LCxis the dominant one influencing hemodynamic condition in proximal LAD (p< 0.05). Based on RRT, the rank of the geometrical factors is:αLAD-LCx>dLMS>lLMS>kLMS, indicating thatαLAD-LCxis the most dominant geometrical factor affecting hemodynamics at proximal LAD which may influence atherosclerosis.Conclusion. The proposed identification of the rank of geometrical features of LCA and the dominant feature may assist clinicians in predicting the possibility of atherosclerosis, of an individual, long before it will occur. This study can further be translated to be used to rank the influence of several arterial geometrical features at different arterial locations to explore detailed relationships between the arterial geometrical features and local hemodynamics.

Protective role of CXCR7 activation in neonatal hyperoxia-induced systemic vascular remodeling and cardiovascular dysfunction in juvenile rats

Neonatal hyperoxia induces long-term systemic vascular stiffness and cardiovascular remodeling, but the mechanisms are unclear. Chemokine receptor 7 (CXCR7) represents a key regulator of vascular homeostasis and repair by modulating TGF-β1 signaling. This study investigated whether pharmacological CXCR7 agonism prevents neonatal hyperoxia-induced systemic vascular stiffness and cardiac dysfunction in juvenile rats. Newborn Sprague Dawley rat pups assigned to room air or hyperoxia (85% oxygen), received CXCR7 agonist, TC14012 or placebo for 3 weeks. These rat pups were maintained in room air until 6 weeks when aortic pulse wave velocity doppler, cardiac echocardiography, aortic and left ventricular (LV) fibrosis were assessed. Neonatal hyperoxia induced systemic vascular stiffness and cardiac dysfunction in 6-week-old rats. This was associated with decreased aortic and LV CXCR7 expression. Early treatment with TC14012, partially protected against neonatal hyperoxia-induced systemic vascular stiffness and improved LV dysfunction and fibrosis in juvenile rats by decreasing TGF-β1 expression. In vitro, hyperoxia-exposed human umbilical arterial endothelial cells and coronary artery endothelial cells had increased TGF-β1 levels. However, treatment with TC14012 significantly reduced the TGF-β1 levels. These results suggest that dysregulation of endothelial CXCR7 signaling may contribute to neonatal hyperoxia-induced systemic vascular stiffness and cardiac dysfunction.

Assessment of the Dimensions of Coronary Arteries for the Manifestation of Coronary Artery Disease

INTRODUCTION

The size of the coronary artery influences the effective outcome of therapeutic measures like coronary artery bypass graft (CABG) surgery, percutaneous coronary interventions (PCI), and diagnosis of coronary artery disease. Patients' age, gender, BMI, anatomical variations, and increased left ventricular size all have an effect on coronary artery parameters.

OBJECTIVE

This study aims to compare the average size of the coronary arteries of the Pakistani population in both sexes for manifestation of coronary artery disease.

METHODOLOGY

For the analysis of the coronary arteries, 100 patients of both sexes, male and female, were taken. X-ray angiography was performed for two-dimensional images of coronary arteries. For diameter measurement, images were visualized on quantitative coronary angiography (QCA) in different views (caudal and cranial views). The diameters of the left main coronary artery (left main stem/LMS), left anterior descending (LAD), left circumflex (LCx), and right coronary artery (RCA) were measured on angiograms. Data about the dimensions of the coronary artery was gathered through quantitative angiography. Data analysis was done through SPSS version 26 (IBM Corp., Armonk, NY).

RESULTS

 There is a notable distinction in the average diameters among the proximal LAD (3.12), mid-LAD (2.40), and distal LAD (1.29). A statistically significant difference is evident among mid-LCx, distal LCx, and proximal LCx (p-value < 0.001). Likewise, the average diameter of the distal RCA (1.89) was smaller when compared to the mid-RCA (3.19) and proximal RCA (3.78). However, there was no significant difference in the average diameter among mid-LMS, distal LMS, and proximal LMS (p-value = 0.09).

CONCLUSION

The average diameter of distal RCA was smaller when compared to mid-RCA and proximal RCA. The average size of proximal LAD and proximal LCx was comparatively larger than mid- and distal LAD and LCx. The findings of current research will be beneficial for the diagnosis and management of coronary artery disease patients.

Associations between physical activity and cardiorespiratory fitness with vascular health phenotypes in older adults: a cross-sectional study

Objective: We investigated the associations between physical activity (PA) and cardiorespiratory fitness (CRF) with vascular health phenotypes in community-dwelling older adults. Methods: This cross-sectional study included 82 participants (66.8 ± 5.2 years; 81% females). Moderate-to-vigorous physical activity (MVPA) was assessed using accelerometers, and CRF was measured using the distance covered in the 6-min walk test (6MWT). The vascular health markers were as follows: i) arterial function measured as aortic pulse wave velocity (aPWV) estimated using an automatic blood pressure device; and ii) arterial structure measured as the common carotid intima-media thickness (cIMT). Using a combination of normal cIMT and aPWV values, four groups of vascular health phenotypes were created: normal aPWV and cIMT, abnormal aPWV only, abnormal cIMT only, and abnormal aPWV and cIMT. Multiple linear regression was used to estimate the beta coefficients (β) and their respective 95% confidence intervals (95% CI) adjusting for BMI, and medication for diabetes, lipid, and hypertension, sex, age, and blood pressure. Results: Participants with abnormal aPWV and normal cIMT (β = -53.76; 95% CI = -97.73--9.78 m; p = 0.017), and participants with both abnormal aPWV and cIMT (β = -71.89; 95% CI = -125.46--18.31 m; p = 0.009) covered less distance in the 6MWT, although adjusting for age, sex and blood pressure decreased the strength of the association with only groups of abnormal aPWV and cIMT covering a lower 6MWT distance compared to participants with both normal aPWV and cIMT (β = -55.68 95% CI = -111.95-0.59; p = 0.052). No associations were observed between MVPA and the vascular health phenotypes. Conslusion: In summary, poor CRF, but not MVPA, is associated with the unhealthiest vascular health phenotype (abnormal aPWV/cIMT) in older adults.

Gender Specific Coronary Artery Diameters in CT Coronary Angiogram: A Comparative Study in Female and Male Population

Objectives:

Women show significant in-hospital morbidity and mortality with greater extent of symptoms, poorer post-revascularization outcome with increased restenosis and repeat revascularization after angioplasty, than men. Smaller sized coronary arteries in females can be attributable for this differential outcome, which is also similar in case of Indians, compared to Caucasians. Our aim is to assess the gender-specific difference in coronary arteries using noninvasive Multidetector Computed-Tomography Coronary-Angiogram(CT-CAG) and comparing the same with other racial database.

Materials and Methods:

With Ethics committee approval, present retrospective comparative study conducted in 128CT-CAG scans in 18-45years aged 100 women and 89 men with no atherosclerotic burden excluding pathological coronaries and high calcium score>100. Diameter measurements of proximal (≤10mm) segments of right coronary artery(RCA), left main coronary artery(LMCA), left anterior descending(LAD) and circumflex(LCx) arteries were taken, averaged and compared using 2-sample z-test. Considering the obtained mean diameters of total sample as South-Indian dataset which is then compared with Caucasians dataset taken from previous study.

Results:

Women showed smaller coronary artery diameters compared to men in all the arteries, with greater gender-specific age-adjusted difference in LMCA, followed by LAD, RCA and least in LCX. South-Indians showed statistically significant smaller diameters of all the coronary arteries compared to Caucasians.

Conclusion:

Gender-specific difference among the coronary arteries does exist, with females having smaller dimensions; South-Indians also show smaller diameters. This warrants a clinician for gender-specific approaches during the interventions because of technical difficulties.

Long-Term Excessive Dietary Phosphate Intake Increases Arterial Blood Pressure, Activates the Renin-Angiotensin-Aldosterone System, and Stimulates Sympathetic Tone in Mice

Increased dietary phosphate intake has been associated with severity of coronary artery disease, increased carotid intima–media thickness, left ventricular hypertrophy (LVH), and increased cardiovascular mortality and morbidity in individuals with normal renal function as well as in patients suffering from chronic kidney disease. However, the underlying mechanisms are still unclear. To further elucidate the cardiovascular sequelae of long-term elevated phosphate intake, we maintained male C57BL/6 mice on a calcium, phosphate, and lactose-enriched diet (CPD, 2% Ca, 1.25% P, 20% lactose) after weaning them for 14 months and compared them with age-matched male mice fed a normal mouse diet (ND, 1.0% Ca, 0.7% P). Notably, the CPD has a balanced calcium/phosphate ratio, allowing the effects of elevated dietary phosphate intake largely independent of changes in parathyroid hormone (PTH) to be investigated. In agreement with the rationale of this experiment, mice maintained on CPD for 14 months were characterized by unchanged serum PTH but showed elevated concentrations of circulating intact fibroblast growth factor-23 (FGF23) compared with mice on ND. Cardiovascular phenotyping did not provide evidence for LVH, as evidenced by unchanged LV chamber size, normal cardiomyocyte area, lack of fibrosis, and unchanged molecular markers of hypertrophy (Bnp) between the two groups. However, intra-arterial catheterization revealed increases in systolic pressure, mean arterial pressure, and pulse pressure in mice fed the CPD. Interestingly, chronically elevated dietary phosphate intake stimulated the renin–angiotensin–aldosterone system (RAAS) as evidenced by increased urinary aldosterone in animals fed the CPD, relative to the ND controls. Furthermore, the catecholamines epinephrine, norepinephrine, and dopamine as well as the catecholamine metabolites metanephrine. normetanephrine and methoxytyramine as measured by mass spectrometry were elevated in the urine of mice on CPD, relative to mice on the ND. These changes were partially reversed by switching 14-month-old mice on CPD back to ND for 2 weeks. In conclusion, our data suggest that excess dietary phosphate induces a rise in blood pressure independent of secondary hyperparathyroidism, and that this effect may be mediated through activation of the RAAS and stimulation of the sympathetic tone.

Age and Blood Pressure Contribute to Aortic Cell and Tissue Stiffness Through Distinct Mechanisms

BACKGROUND

Aortic stiffening is strongly associated with both aging and hypertension, but the underlying mechanisms remain unclear. We hypothesized that aging-induced aortic stiffness is mediated by a mechanism differing from hypertension.

METHODS

We conducted comprehensive in vivo and in vitro experiments using multiple rat models to dissect the different mechanisms of aortic stiffening mediated by aging and hypertension.

RESULTS

A time-course study in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) normotensive rats showed more pronounced aging-associated aortic stiffening in SHR versus WKY. Angiotensin II-induced hypertension was associated with more significant aortic stiffening in older versus young WKY rats. Hypertension aggravated aging effects on aortic wall thickness and extracellular matrix content, indicating combinational effects of aging and hypertension on aortic stiffening. Intrinsic stiffness of isolated aortic vascular smooth muscle cells (VSMCs) increased with age in WKY rats, although no significant difference between older SHR and older WKY VSMCs was observed in 2-dimensional culture, reconstituted 3-dimensional tissues were stiffer for older SHR versus older WKY. A selective inhibitor that reduced hypertension-mediated aortic stiffening did not decrease age-related stiffening in aortic VSMCs and aortic wall. Integrin β1 and SM22 (smooth muscle-specific SM22 protein) expression were negligibly changed in WKY VSMCs during aging but were markedly increased by hypertension in older versus young WKY VSMCs. A notable shift of filamin isoforms from B to A was detected in older WKY VSMCs.

CONCLUSIONS

Our results indicate distinct mechanisms mediating aging-associated aortic VSMC and vessel stiffness, providing new insights into aortic stiffening and the pathogenesis of hypertension in the elderly.

Association of waist-to-height ratio with hypertension and its subtypes in southern China

Data regarding the association of the waist-to-height ratio (WHtR) with hypertension (HTN) are conflicting. Moreover, little information is available on the association between WHtR and HTN subtypes. Therefore, we aimed to investigate the associations between WHtR and the prevalence of HTN and its subtypes in a Chinese population. In the cross-sectional analysis, 13,947 adults from the China Hypertension Survey study were analysed. We examined the relationship between WHtR and the prevalence of HTN and its subtypes (isolated systolic hypertension (ISH), isolated diastolic hypertension (IDH) and systodiastolic hypertension (SDH)) using multivariate logistic regression analysis. A generalized additive model (GAM) and smooth curve fitting (penalized spline method) were also used. Overall, the mean WHtR was 0.50. The adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for HTN, ISH, IDH and SDH for each standard deviation (SD) increase in WHtR were 1.53 (1.45-1.61), 1.36 (1.28-1.44), 1.41 (1.20-1.65) and 1.47 (1.36-1.59), respectively. The fully adjusted smooth curve fitting revealed a linear association between WHtR and HTN, ISH, IDH, and SDH. Moreover, the positive associations between WHtR and HTN and its subtypes were more strong among younger adults (<60 compared with ≥60 years, P values for interaction <0.001). These findings suggested that WHtR was positively associated with HTN and its subtypes, especially among younger adults (<60 years) in southern China.

Applicability of the single-layer flat-coil-oscillator technology-based vibration and vibro-acoustic sensors in medical and biological study of the cardiovascular system: Advantages and perspectives of the carotid pulse wave registration

The possibility and feasibility of using the single-layer flat-coil-oscillator (SFCO) technology-based vibration and vibro-acoustic sensors in diagnostic devices and biomedical studies of the cardiovascular system are discussed in this paper. Using an example of recording pulse waves of left carotid artery and their analysis, the information content of the data recorded by these sensors in a number of cases is shown-assessment of age-related changes in the stiffness of the vascular wall, assessment of the dynamics of systolic volume, reflecting myocardial contractility, and rhythm disturbance (extra-systole and arrhythmia). These sensors are shown to be promising in recording heart sounds due to their high sensitivity. The possibility of assessing the dynamics of relaxation of the cardiovascular system after exercise (stress test) is shown. The advantages of using SFCO vibration and vibro-acoustic sensors are high sensitivity, ease of use, and no need to train specialists. These advantages open new perspectives for their implementation in mobile wearable "smart" devices for individual monitoring.

Associations of residential walkability and greenness with arterial stiffness in the UK Biobank

BACKGROUND

Arterial stiffness is a key non-invasive marker of early vascular ageing, however, little is known of its associations with urban built environment. We examined the associations of objectively-measured residential walkability and greenness with arterial stiffness in a large UK-wide population cohort.

METHODS

We employed data from the baseline UK Biobank cohort comprising adult participants recruited over the period of 2006 to 2010. Residential walkability index, defined as a function of density (residential, retail and public transit), street-level design, and destination accessibility was measured using a 1-Km dwelling catchment, while greenness was modelled as the mean Normalized Difference Vegetation Index (NDVI) of 0.5-metre resolution assessed within a 0.5-Km catchment. Arterial stiffness index (ASI) was measured non-invasively from the pulse waveform. Linear regression models were developed to examine associations of walkability and greenness with arterial stiffness. Restricted cubic spline (RCS) models were developed to examine dose-response relationships. We also examined effect modifications by sex and age, as well as the interaction effect of greenness and walkability.

RESULTS

This cross-sectional study used a target sample of 169,704 UK Biobank participants aged ≥ 39 years. After full adjustments, in reference to the lowest walkability exposure quartile, those in the highest were associated with lower ASI (β = -0.083 m/s, 95% CI: -0.14 to -0.03, p = 0.005). Participants in the third and fourth NDVI greenness exposure quartiles were also associated with lower ASI (β = -0.074 m/s, -0.14 to -0.01, p < 0.020 for the third and β = -0.293 m/s, -0.36 to -0.23, p < 0.001 for the fourth quartiles in reference to the first). The inverse association between NDVI greenness and ASI was more pronounced among women (p < 0.001), older adults (p = 0.011) and among participants in the highest walkability quartile (p < 0.001).

CONCLUSION

Designing more walkable and greener residential environments can be a preventive intervention aimed at lowering the population distribution of vascular ageing and associated cardiovascular risks.

An Exploratory Study on the Relationship between Brachial Arterial Blood Flow and Cardiac Output

Background

We have obtained prospective clinical outcomes using the brachial artery largely, such as Korotkoff sound and vasomotor function measurement by ultrasound guidance to predict the prognosis of cardiovascular diseases. Very few reports on the quantitative measurement of the relationship between the brachial artery blood flow and cardiac output have been reported.

Purpose

(1) To investigate whether the quantitative relationship between the brachial artery blood flow and cardiac output existed. (2) To provide a theoretical basis for taking advantage of artificial intelligence (AI) using Korotkoff sound analogously as far as possible to predict the cardiac output.

Methods

A total of 586 patients who underwent cardiac color ultrasound in our center from 2021.3 to 2021.7 were included for analyses. The vascular parameters of the right upper limb brachial artery (such as the Diameter, Area, Blood Velocity, and Flow) were measured immediately after the cardiac color ultrasound, and some basic clinical parameters (Age, Sex, BMI, and Disease) were recorded subsequently. Ultimately, the Mann-Whitney and independent sample T-test were used to analyze the data.

Results

(1) The mean Rate of the brachial arterial blood flow to cardiac output was 1.23%, and the mean 95% CI was (1.18%, 1.29%), indicating that the value was mainly concentrated in the current value interval. The indicator demonstrates that there is no significant difference currently among the patients with hypertension, coronary heart disease, and cardiac dysfunction. (2) The brachial artery wall diameter (Dist) is significantly thicker in patients with coronary heart disease and hypertension compared to patients with other cardiovascular diseases. (3) Cardiac output augments remarkably in patients with hypertension.

Conclusion

Our study suggests that the Rate (brachial artery blood flow/cardiac output) is a constant of 1.23% approximately. It provides a theoretical basis for the subsequent application of the artificial intelligence (AI) method to predict heart function using Korotkoff sound, cope with large computational amounts, and improve computational speed. It is also indirectly proved that hypertension can lead to a change in peripheral vascular hyperplasia and increase cardiac output.

Caloric restriction enhances vascular tone of cerebral and mesenteric resistance arteries in aged rats

Vascular changes of tone and biomechanical properties induced by ageing increase the risk for cardiovascular diseases. Caloric restriction (CR) has been shown to protect against cardiovascular diseases and improve endothelial dysfunction in cerebral resistance arteries. We hypothesise that CR will enhance vascular tone and structural properties of cerebral resistance arteries and exert comparable beneficial effects on the systemic vasculature of aged rat model. Eighteen-month-old male Sprague-Dawley rats were feed either ad libitum or restricted to 60 % of calorie consumption up to 24 months of age, when body weight (BW) measurements were taken and functional and structural properties of resistance arteries were assessed using a pressure myograph. In cerebral arteries, CR increased myogenic tone (p < 0.001) and distensibility (p < 0.01) in response to intraluminal pressure and concentration-dependent constriction to KCl (p < 0.001). In mesenteric arteries constriction in response to KCl was increased (p < 0.0001) and wall thickness reduced (p < 0.01) in CR rats. BW was reduced (p < 0.0001) in FR rats. Our findings demonstrate that CR improves vascular tone of resistance arteries regardless the type of stimulus and independently of the vascular bed. CR may be a beneficial dietary approach to prevent age-related vascular diseases.

New indicators for systematic assessment of aortic morphology: a narrative review

In order to prevent the occurrence of aortic adverse events in ascending thoracic aortic aneurysm patients, preventive surgery is the sole option in case of large aneurysm. Identifying high-risk patients timely and accurately requires effective predictive indicators of aortic adverse events and accurate risk stratification thresholds. Absolute diameter measured after a single imaging examination, which has been used as the predictive indicator for decades, has been proved to be ineffective for risk stratification in moderately dilated aorta. Previously, new indicators combining absolute diameters with personalized parameters have been reported to show better predictive power of aortic adverse events than absolute diameters by correcting the effect of these parameters on the diameters. Meanwhile, combining three-dimensional parameters to formulate risk stratification thresholds not only may characterize the aortic risk morphology more precisely, but also predict aortic adverse events more accurately. These new indicators may provide more systematic assessment methods of patients’ risk, formulate more personalized intervention strategies for ascending thoracic aortic aneurysm patients, and also provide a basis for researchers to develop more accurate and effective risk thresholds. We also highlight that the algorithm obtained by combining multiple indicators may be a better choice compared with single indicator, but this still requires the support of more evidence. Due to the particularity of syndromic aortic disease, whether these new indicators can be used for its risk stratification is still uncertain. Therefore, the scope of this manuscript does not include this kind of disease.

Neonatal hyperoxia exposure induces aortic biomechanical alterations and cardiac dysfunction in juvenile rats

Supplemental oxygen (O₂) therapy in preterm infants impairs lung development, but the impact of O₂ on long‐term systemic vascular structure and function has not been well‐explored. The present study tested the hypothesis that neonatal O₂ therapy induces long‐term structural and functional alterations in the systemic vasculature, resulting in vascular stiffness observed in children and young adults born preterm. Newborn Sprague‐Dawley rats were exposed to normoxia (21% O₂) or hyperoxia (85% O₂) for 1 and 3 weeks. A subgroup exposed to 3 weeks hyperoxia was recovered in normoxia for an additional 3 weeks. Aortic stiffness was assessed by pulse wave velocity (PWV) using Doppler ultrasound and pressure myography. Aorta remodeling was assessed by collagen deposition and expression. Left ventricular (LV) function was assessed by echocardiography. We found that neonatal hyperoxia exposure increased vascular stiffness at 3 weeks, which persisted after normoxic recovery at 6 weeks of age. These findings were accompanied by increased PWV, aortic remodeling, and altered LV function as evidenced by decreased ejection fraction, cardiac output, and stroke volume. Importantly, these functional changes were associated with increased collagen deposition in the aorta. Together, these findings demonstrate that neonatal hyperoxia induces early and sustained biomechanical alterations in the systemic vasculature and impairs LV function. Early identification of preterm infants who are at risk of developing systemic vascular dysfunction will be crucial in developing targeted prevention strategies that may improve the long‐term cardiovascular outcomes in this vulnerable population.

New progress on the study of aortic stiffness in age-related hypertension

: Hypertension is a worldwide known cause of morbidity and mortality in the elderly and is a major risk factor for cardiovascular complications such as stroke, myocardial infarction, renal complications and heart failure. Although the mechanisms of hypertension remain largely unknown, a recent new concept is that aortic stiffening is a cause of hypertension in middle-aged and older individuals, which highlighted the importance of aortic stiffening in the development of age-related hypertension. Understanding the pathogenesis of aortic stiffness therefore became one of the important approaches to preventing and controlling hypertension. This review discusses the recent progress of the potential causes of aortic stiffening and its implication on the pathogenesis of hypertension, in terms of aging, inflammation, metabolic syndromes, neuroendocrine and the interaction among these causes.

Clinical Research on the Aortic Elasticity in Patients with Type 1 Diabetes Mellitus Complicated with Hypertension

OBJECTIVE

To investigate the characteristics of aortic elasticity in type 1 diabetes mellitus (DM1) patients with hypertension using dual-source computed tomography (DSCT).

METHODS

Subjects were divided into four groups: 31 with hypertension (EH group), 28 with DM1 (DM1 group), 30 with hypertension and DM1 (DM1 + EH group), and 30 healthy volunteers (control group, CG). ECG-gated DSCT was used to measure the cross-sectional area of the aorta in diastole and systole and calculate the aortic elasticity (D). Analysis of variance and multiple linear regression were used for statistical analysis.

RESULTS

Compared with the CG, aortic elasticity (D) in the DM1 group patients was not significantly decreased. Compared with the EH group, the DM1 + EH group showed no significant change. The aortic elasticity (D) in the EH and DM1 + EH groups was significantly lower than that in the CG and DM1 group.

CONCLUSION

DM1 slightly affects the aortic elasticity of the descending aorta, whereas hypertension exerts the main effect.

A multi-ancestry genome-wide study incorporating gene-smoking interactions identifies multiple new loci for pulse pressure and mean arterial pressure

Elevated blood pressure (BP), a leading cause of global morbidity and mortality, is influenced by both genetic and lifestyle factors. Cigarette smoking is one such lifestyle factor. Across five ancestries, we performed a genome-wide gene-smoking interaction study of mean arterial pressure (MAP) and pulse pressure (PP) in 129 913 individuals in stage 1 and follow-up analysis in 480 178 additional individuals in stage 2. We report here 136 loci significantly associated with MAP and/or PP. Of these, 61 were previously published through main-effect analysis of BP traits, 37 were recently reported by us for systolic BP and/or diastolic BP through gene-smoking interaction analysis and 38 were newly identified (P < 5 × 10-8, false discovery rate < 0.05). We also identified nine new signals near known loci. Of the 136 loci, 8 showed significant interaction with smoking status. They include CSMD1 previously reported for insulin resistance and BP in the spontaneously hypertensive rats. Many of the 38 new loci show biologic plausibility for a role in BP regulation. SLC26A7 encodes a chloride/bicarbonate exchanger expressed in the renal outer medullary collecting duct. AVPR1A is widely expressed, including in vascular smooth muscle cells, kidney, myocardium and brain. FHAD1 is a long non-coding RNA overexpressed in heart failure. TMEM51 was associated with contractile function in cardiomyocytes. CASP9 plays a central role in cardiomyocyte apoptosis. Identified only in African ancestry were 30 novel loci. Our findings highlight the value of multi-ancestry investigations, particularly in studies of interaction with lifestyle factors, where genomic and lifestyle differences may contribute to novel findings.

Nonlinear Brillouin spectroscopy: what makes it a better tool for biological viscoelastic measurements

Brillouin spectroscopy is an emerging tool in biomedical imaging and sensing. It is capable of assessing the high-frequency viscoelastic longitudinal modulus with microscopic spatial resolution. Nonlinear Brillouin spectroscopy based on impulsive stimulated Brillouin scattering offers a number of significant advantages over conventional spontaneous and stimulated Brillouin scattering. In this report, we evaluate the accuracy of Brillouin shift measurements in spontaneous and nonlinear Brillouin microscopy by calculating the Allan variance for both CW excited spontaneous Brillouin measurements and nonlinear Brillouin scattering measurements made with both nanosecond and picosecond pulse excitation. We find that impulsive stimulated Brillouin spectroscopy is superior to spontaneous Brillouin spectroscopy in terms of the accuracy of such measurements and demonstrate its application for assessing tiny changes in Brillouin frequency shifts associated with low concentrations of biologically relevant solutions.

Effects of allisartan isoproxil on blood pressure and target organ injury in patients with mild to moderate essential hypertension

Evidence has shown that angiotensin II type 1 receptor antagonists have lower blood pressure and have target organ protective effects, but this is not the case for the drug allisartan isoproxil. The aim of this study was to evaluate the effects of allisartan isoproxil on blood pressure and target organ injury in patients with mild to moderate essential hypertension.In total, 80 essential hypertensive participants were randomly divided into an allisartan group and a nifedipine group (n = 40 per group), and their blood pressure was measured once per month for 6 months. A 2-dimensional echocardiogram was performed at baseline and at the end of the study. The serum levels of renal injury indexes, endothelial function markers, inflammatory factors, blood biochemical assays and urinary measurements were determined at baseline and at 6 months.At the end of the study, both systolic and diastolic blood pressure were significantly decreased in the allisartan group compared with baseline and showed the same antihypertensive effect as the nifedipine group. Meanwhile, the left ventricular remodeling, 24-hours levels of urinary microalbumin, endothelial dysfunction, and arterial stiffness were all significantly improved compared with that of the baseline and the nifedipine group (all P < .05).The present study showed that allisartan isoproxil had favorable blood pressure lowering and heart, renal, and endothelial protective effects in patients with mild to moderate essential hypertension.

Arterial stiffness and hypertension status in Afro-Caribbean men

OBJECTIVE

African ancestry individuals are at high risk for hypertensive cardiovascular disease (CVD) and could benefit from early detection of arterial stiffening. We tested the association between the 2017 ACC/AHA hypertension categorizations, which include new blood pressure (BP) cutoffs and a definition for elevated BP, and arterial stiffness in 772 Afro-Caribbean men aged 50+ years (mean 64 years).

METHODS

Arterial stiffness was assessed by brachial-ankle pulse-wave velocity (PWV) using a waveform analyzer. Hypertension groups were based on the 2017 ACC/AHA guidelines and by pharmacologic control status. Multiple linear/logistic regression was used to determine the association of PWV with BP and hypertension.

RESULTS

Mean (SD) PWV was 1609 (298) cm/s and was independently correlated with age, SBP, pulse, diabetes, height, and alcohol intake (all P < 0.02). After adjusting for these, in men aged at least 65 years, those with stage 1 or uncontrolled stage 2 hypertension had significantly greater PWV than all other groups (all P < 0.05). Men with controlled hypertension had similar PWV to those with elevated BP (P = 0.7); however, this was significantly greater than men with normal BP (all P < 0.05). Patterns were similar, but with smaller effect sizes, in men aged less than 65 years (all P < 0.05 except controlled hypertension versus elevated or normal BP were not significant).

CONCLUSION

In these high-risk Afro-Caribbeans: stage 1 hypertension is associated with increased PWV, which supports the new guidelines; and, pharmacologic control appears to partially protect men from increased PWV. Longitudinal studies are needed to determine optimal PWV and timing of antihypertensive treatment for preventing future CVD.

Factors associated with the severity of hypertension among Malaysian adults

High blood pressure is a worldwide problem and major global health burden. Whether alone or combined with other metabolic diseases, high blood pressure increases the risk of cardiovascular disease. This study is a secondary data analysis from the National Health and Morbidity Survey 2015, a population-based study that was conducted nationwide in Malaysia using a multi-stage stratified cluster sampling design. A total of 15,738 adults ≥18-years-old were recruited into the study, which reports the prevalence of hypertension stages among adults in Malaysia using the JNC7 criteria and determinants of its severity. The overall prevalence of raised blood pressure was 66.8%, with 45.8% having prehypertension, 15.1% having Stage 1 hypertension, and 5.9% having Stage 2 hypertension. In the multivariate analysis, a higher likelihood of having prehypertension was observed among respondents with advancing age, males (OR = 2.74, 95% CI: 2.41-3.12), Malay ethnicity (OR = 1.21, 95% CI: 1.02-1.44), lower socioeconomic status, and excessive weight. The factors associated with clinical hypertension (Stages 1 and 2) were older age, rural residency (Stage 1 OR = 1.22, Stage 2 OR = 1.28), Malay ethnicity (Stage 2 OR = 1.64), diabetes (Stage 2 OR = 1.47), hypercholesterolemia (Stage 1 OR = 1.34, Stage 2 OR = 1.82), being overweight (Stage 1 OR = 2.86, Stage 2 OR = 3.44), obesity (Stage 1 OR = 9.01, Stage 2 OR = 13.72), and lower socioeconomic status. Almost 70% of Malaysian adults are at a risk of elevated blood pressure. The highest prevalence was in the prehypertension group, which clearly predicts a future incurable burden of the disease. Public health awareness, campaigns through mass and social media, and intervention in the work place should be a priority to control this epidemic.

The effect of age and gender on tortuosity of the descending thoracic Aorta

BACKGROUND

To study the effect of age and gender on tortuosity of the descending thoracic aorta, and to evaluate inter-observer agreement of tortuosity index (TI) measurements.

METHODS

Contrast-enhanced CT scans of 182 patients were analyzed by an experienced radiologist using routine 3D imaging software. The descending aorta was defined by proximal and distal endpoints. The software generated centerline length, and straight line distance between the 2 endpoints were measured. TI was calculated as: [centerline length / straight line distance -1] * 100. Impact of age on TI of the descending aorta was assessed using linear regression in both genders. To assess inter-observer agreement; TI measurements of 50 cases were repeated by 3 other independent readers.

RESULTS

The mean (±SD) TI was 8.3 ± 2.6 in men and 8.9 ± 3 in women, with no significant difference between the 2 genders, p = 0.208. Moderate positive correlation was observed between TI and age (r = 0.566, p < 0.00001 and r = 0.569, p < 0.00001 in men and women, respectively). The 10-year-percent change was higher in women than men (13.3% and 9.5%, respectively). Inter-observer agreement for TI was good, intra-class correlation coefficient was 0.84 (95% CI: 0.76-0.89, p < 0.0001). Centerline length was poorly correlated to age (r = 0.248, p = 0.048 in men and r = 0.369, p < 0.001 in women). Body-surface-area-indexed centerline length was not significantly correlated to age (p = 0.948).

CONCLUSIONS

Tortuosity of the descending aorta increases with age in both genders. TI has acceptable inter-observer agreement and was better correlated to age than centerline length measurements.

Altered Placental Chorionic Arterial Biomechanical Properties During Intrauterine Growth Restriction

Intrauterine growth restriction (IUGR) is a pregnancy complication due to placental dysfunction that prevents the fetus from obtaining enough oxygen and nutrients, leading to serious mortality and morbidity risks. There is no treatment for IUGR despite having a prevalence of 3% in developed countries, giving rise to an urgency to improve our understanding of the disease. Applying biomechanics investigation on IUGR placental tissues can give important new insights. We performed pressure-diameter mechanical testing of placental chorionic arteries and found that in severe IUGR cases (RI > 90th centile) but not in IUGR cases (RI < 90th centile), vascular distensibility was significantly increased from normal. Constitutive modeling demonstrated that a simplified Fung-type hyperelastic model was able to describe the mechanical properties well, and histology showed that severe IUGR had the lowest collagen to elastin ratio. To demonstrate that the increased distensibility in the severe IUGR group was related to their elevated umbilical resistance and pulsatility indices, we modelled the placental circulation using a Windkessel model, and demonstrated that vascular compliance (and not just vascular resistance) directly affected blood flow pulsatility, suggesting that it is an important parameter for the disease. Our study showed that biomechanics study on placenta could extend our understanding on placenta physiology.

l-Citrulline Supplementation: Impact on Cardiometabolic Health

Diminished bioavailability of nitric oxide (NO), the gaseous signaling molecule involved in the regulation of numerous vital biological functions, contributes to the development and progression of multiple age- and lifestyle-related diseases. While l-arginine is the precursor for the synthesis of NO by endothelial-nitric oxide synthase (eNOS), oral l-arginine supplementation is largely ineffective at increasing NO synthesis and/or bioavailability for a variety of reasons. l-citrulline, found in high concentrations in watermelon, is a neutral alpha-amino acid formed by enzymes in the mitochondria that also serves as a substrate for recycling l-arginine. Unlike l-arginine, l-citrulline is not quantitatively extracted from the gastrointestinal tract (i.e., enterocytes) or liver and its supplementation is therefore more effective at increasing l-arginine levels and NO synthesis. Supplementation with l-citrulline has shown promise as a blood pressure lowering intervention (both resting and stress-induced) in adults with pre-/hypertension, with pre-clinical (animal) evidence for atherogenic-endothelial protection. Preliminary evidence is also available for l-citrulline-induced benefits to muscle and metabolic health (via vascular and non-vascular pathways) in susceptible/older populations. In this review, we examine the impact of supplementing this important urea cycle intermediate on cardiovascular and metabolic health outcomes and identify future directions for investigating its therapeutic impact on cardiometabolic health.

Rho Kinase Regulates Aortic Vascular Smooth Muscle Cell Stiffness Via Actin/SRF/Myocardin in Hypertension

Background/Aims:

Our previous studies demonstrated that intrinsic aortic smooth muscle cell (VSMC) stiffening plays a pivotal role in aortic stiffening in aging and hypertension. However, the underlying molecular mechanisms remain largely unknown. We here hypothesized that Rho kinase (ROCK) acts as a novel mediator that regulates intrinsic VSMC mechanical properties through the serum response factor (SRF)/myocardin pathway and consequently regulates aortic stiffness and blood pressure in hypertension.

Methods:

Four-month old male spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats were studied. Aortic stiffness was measured by echography. Intrinsic mechanical properties of VSMCs were measured by atomic force microscopy (AFM) in vitro.

Results:

Compared to WKY rats, SHR showed a significant increase in aortic stiffness and blood pressure, which is accompanied by a remarkable cell stiffening and ROCK activation in thoracic aortic (TA) VSMCs. Theses alterations in SHR were abolished by Y-27632, a specific inhibitor of ROCK. Additionally, boosted filamentous/globular actin ratio was detected in TA VSMCs from SHRversus WKY rats, resulting in an up-regulation of SRF and myocardin expression and its downstream stiffness-associated genes including α-smooth muscle actin, SM22, smoothelin and myosin heavy chain 11. Reciprocally, these alterations in SHR TA VSMCs were also suppressed by Y-27632. Furthermore, a specific inhibitor of SRF/myocardin, CCG-100602, showed a similar effect to Y-27632 in SHR in both TA VSMCs stiffness in vitro and aorta wall stiffness in vivo.

Conclusion:

ROCK is a novel mediator modulating aortic VSMC stiffness through SRF/myocardin signaling which offers a therapeutic target to reduce aortic stiffening in hypertension.

Ultrastructural and histomorphologic properties of the internal thoracic artery: implications for coronary revascularization

Coronary artery disease represents a major health problem worldwide for which coronary artery bypass surgery remains a standard of care. Among the several grafts that are available, the internal thoracic artery (ITA) has long been considered the best as several advantages have been described compared with other vessels (e.g. saphenous vein or radial artery), namely, an absent to minor atherosclerotic development. In fact, several studies showed the presence of preatherosclerotic lesions, such as intimal and/or medial thickening, medial fibrosis, among others, in the presence of certain cardiovascular risk factors as well as established atherosclerotic lesions (i.e. type II or more lesions). This paper primarily aimed at reviewing the current knowledge on the histomorphological characteristics of ITA as well as the comparative histomorphology of ITA with other vessel grafts currently in use in coronary surgery. As some of the evidence is not clear or consensual, this paper also aimed at reviewing the main histopathological, histomorphometrical, and ultrastructural findings in ITAs from patients with known cardiovascular risk factors (e.g. aging, obesity, hypertension, diabetes, smoking, and others). As the presence of preatherosclerotic and/or atherosclerotic lesions may compromise the success of the myocardial revascularization and lead to graft failure, contributing toward the associated morbidity and/or mortality, it is essential to improve the scientific knowledge on the structural characterization of ITAs and its correlation with the cardiovascular risk profile.

Oxidative Stress is Closely Associated with Increased Arterial Stiffness, Especially in Aged Male Smokers without Previous Cardiovascular Events: A Cross-Sectional Study

Aim: Cigarette smoking is one of the major risk factors for cardiovascular diseases and induces deleterious vascular damage. Oxidative stress is involved in vascular inflammation, the process of atherosclerosis. The purpose of the present study was to investigate whether the effects of oxidative stress on the arterial wall differ between smokers and non-smokers.

Methods: Male smokers and non-smokers without physical deconditioning who visited Enshu hospital for an annual physical check-up were enrolled in the study. To assess oxidative stress, serum levels of derivative reactive oxygen metabolites (d-ROM) were measured. The radial augmentation index (RAI) was measured using an automated device and was used as an index for arterial stiffness.

Results: Univariate and multivariate linear regression analysis showed that RAI was independently associated with d-ROM levels only in smokers. Moreover, RAI was significantly higher in smokers than in non-smokers. Logistic regression analysis with the endpoint of a higher RAI than the mean revealed that older age (> 65 years), hypertension, and smoking were independently associated with higher RAI. Similarly, logistic regression analysis with the endpoint of higher d-ROM levels than the mean showed that older age and smoking were independently associated with higher d-ROM levels.

Conclusions: Increased RAI is significantly associated with smoking and, in smokers, with increased d-ROM levels. These results suggest that the effects of oxidative stress on arterial properties differ between smokers and non-smokers and that oxidative stress is closely associated with arterial stiffness, especially in smokers.

Associations Between Blood Pressure and Outcomes Among Blacks in the Jackson Heart Study

BACKGROUND

In 2014, new hypertension guidelines liberalized blood pressure goals for persons 60 years and older. Little is known about the implications for blacks.

METHODS AND RESULTS

Using data from 2000 through 2011 for 5280 participants in the Jackson Heart Study, a community-based black cohort in Jackson, Mississippi, we examined whether higher blood pressure was associated with greater risk of mortality and heart failure hospitalization, and whether the risk was the same across age groups. We investigated associations between baseline blood pressure and both mortality and heart failure hospitalization. We also tested for interactions between age and blood pressure in the mortality model. Median systolic and diastolic blood pressures at baseline were 125 mm Hg (25th-75th percentile, 114-137 mm Hg) and 79 mm Hg (72-86 mm Hg), respectively. Median follow-up was 9 years for mortality and 7 years for heart failure hospitalization. After multivariable adjustment, every 10 mm Hg increase in systolic blood pressure was associated with greater risks of mortality (hazard ratio, 1.12; 95% CI, 1.06-1.17) and heart failure hospitalization (1.07; 95% CI, 1.00-1.14). The mortality risk per 10 mm Hg increase in systolic blood pressure was greater in participants younger than 60 years (1.26; 95% CI, 1.13-1.42) than among participants 60 years and older (1.09; 95% CI, 1.03-1.15).

CONCLUSIONS

Adults in all age groups were at greater risk of mortality as systolic blood pressure increased. In the context of the 2014 hypertension guidelines, these findings should be considered when determining treatment goals in black patients.

Anatomical and Functional Estimations of Brachial Artery Diameter and Elasticity Using Oscillometric Measurements with a Quantitative Approach

Noninvasive vascular function measurement plays an important role in detecting early stages of atherosclerosis and in evaluating therapeutic responses. In this regard, recently, new vascular function measurements have been developed. These new measurements have been used to evaluate vascular function in coronary arteries, large aortic arteries, or peripheral arteries. Increasing vascular diameter represents vascular remodeling related to atherosclerosis. Attenuated vascular elasticity may be a reliable marker for atherosclerotic risk assessment. However, previous measurements for vascular diameter and vascular elasticity have been complex, operator-dependent, or invasive. Therefore, simple and reliable approaches have been sought. We recently developed a new automated oscillometric method to measure the estimated area (eA) of a brachial artery and its volume elastic modulus (VE). In this review, we further report on this new measurement and other vascular measurements. We report on the reliability of the new automated oscillometric measurement of eA and VE. Based on our findings, this measurement technique should be a reliable approach, and this modality may have practical application to automatically assess muscular artery diameter and elasticity in clinical or epidemiological settings. In this review, we report the characteristics of our new oscillometric measurements and other related vascular function measurements.

Systemic arterial stiffness in infants with bronchopulmonary dysplasia: potential cause of systemic hypertension

OBJECTIVE

Systemic hypertension is common among preterm infants with severe bronchopulmonary dysplasia (BPD); the exact cause is unknown. The objective of this preliminary hypothesis generating study was to examine systemic arterial structure and vasomotor function in a cohort of preterm infants with severe BPD, using a cohort of preterm infants without BPD and a cohort of term infants for comparison.

STUDY DESIGN

After obtaining informed consent, we measured aortic wall thickness and vasomotor function by ultrasonography in 20 infants with severe BPD, 7 infants with no BPD, and compared them with 20 healthy term infants.

RESULTS

Maximum aortic thickness was significantly higher in infants with BPD (827±163 μm) compared to those with no BPD (674±22 μm) and term infants (657±67 μm) (unadjusted P<0.0001). The input impedance was similarly elevated in the infants with BPD (574±127 dynes s( )cm(-5)) compared to those with no BPD (325±24 dynes s cm(-)(5)) or term infants (328±113 dynes s cm(-)(5)) (unadjusted P<0.0001). Stiffness index was significantly higher in the infants with BPD (3.4±0.6) compared to those with no BPD (2.6±0.3) or term infants (2.3±0.4) (unadjusted P<0.0001). Systemic vascular resistance was also significantly elevated in the infants with BPD. The results remained significant even after adjusting for gestational age and birth weight. Measures of vasomotor function significantly correlated with blood pressure.

CONCLUSION

The aortic wall thickness and vasomotor function are significantly altered in preterm infants with severe BPD. These findings may explain the higher incidence of systemic hypertension in this population.

Midlife Cardiovascular Risk Factors and Late-Life Unrecognized and Recognized Myocardial Infarction Detect by Cardiac Magnetic Resonance: ICELAND-MI, the AGES-Reykjavik Study

Background

Associations of atherosclerosis risk factors with unrecognized myocardial infarction (UMI) are unclear. We investigated associations of midlife risk factors with UMI and recognized MI (RMI) detected 31 years later by cardiac magnetic resonance.

Methods and Results

The Reykjavik Study (1967–1991) collected serial risk factors in subjects, mean (SD) age 48 (7) years. In ICELAND‐MI (2004–2007), 936 survivors (76 (5) years) were evaluated by cardiac magnetic resonance. Analysis included logistic regression and random effects modeling. Comparisons are relative to subjects without MI. At baseline midlife evaluation, a modified Framingham risk score was significantly higher in RMI and in UMI versus no MI (7.4 (6.3)%; 7.1 (6.2)% versus 5.4 (5.8)%, P<0.001). RMI and UMI were more frequent in men (65%, 64% versus 43%; P<0.0001). Baseline systolic and diastolic blood pressure were significantly higher in UMI (138 (17) mm Hg versus 133 (17) mm Hg; P<0.006; 87 (10) mm Hg versus 84 (10) mm Hg; P<0.02). Diastolic BP was significantly higher in RMI (88 (10) mm Hg versus 84 (10) mm Hg; P<0.02). Cholesterol and triglycerides were significantly higher in RMI (6.7 (1.1) mmol/L versus 6.2 (1.1) mmol/L; P=0.0005; and 1.4 (0.7) mmol/L versus 1.1 (0.7) mmol/L; P<0.003). Cholesterol trended higher in UMI (P=0.08). Serial midlife systolic BP was significantly higher in UMI versus no MI (β [SE] = 2.69 [1.28] mm Hg, P=0.04). Serial systolic and diastolic BP were significantly higher in RMI versus no MI (4.12 [1.60] mm Hg, P=0.01 and 2.05 [0.91] mm Hg, P=0.03) as were cholesterol (0.43 [0.11] mmol/L, P=0.0001) and triglycerides (0.3 [0.06] mmol/L, P<0.0001).

Conclusions

Midlife vascular risk factors are associated with UMI and RMI detected by cardiac magnetic resonance 31 years later. Systolic blood pressure was the most significant modifiable risk factor associated with later UMI.

Hypertension in Malaysia: An Analysis of Trends From the National Surveys 1996 to 2011

This study aimed to determine trends in prevalence, awareness, and control of hypertension in Malaysia and to assess the relationship between socioeconomic determinants and prevalence of hypertension in Malaysia.The distribution of hypertension in Malaysia was assessed based on available data in 3 National Health and Morbidity Surveys (NHMSs) and 1 large scale non-NHMS during the period of 1996 to 2011. Summary statistics was used to characterize the included surveys. Differences in prevalence, awareness, and control of hypertension between any 2 surveys were expressed as ratios. To assess the independent associations between the predictors and the outcome variables, regression analyses were employed with prevalence of hypertension as an outcome variable.Overall, there was a rising trend in the prevalence of hypertension in adults ≥30 years: 32.9% (30%-35.8%) in 1996, 42.6% (37.5%-43.5%) in 2006, and 43.5% (40.4%-46.6%) in 2011. There were significant increase of 32% from 1996 to 2011 (P < 0.001) and of 29% from 1996 to 2006 (P < 0.05), but only a small change of 1% from 2006 to 2011 (P = 0.6). For population ≥18 years, only a 1% increase in prevalence of hypertension occurred from the 2006 NHMS (32.2%) to the 2011 NHMS (32.7%) (P = 0.25). A relative increase of 13% occurred in those with primary education (P < 0.001) and a 15% increase was seen in those with secondary education (P < 0.001). The rate of increase in the prevalence of hypertension in the population with income level RM 3000-3999 was the highest (18%) during this period. In general, the older age group had higher prevalence of hypertension in the 2006 and 2011 NHMSs. The prevalence peaked at 74.1% among population aged 65 to 69 years in the 2011 NHMS. Both the proportion of awareness and the control of hypertension in Malaysia improved from 1996 to 2006. A change in the control of hypertension was 13% higher in women than in men.The findings suggest that the magnitude of hypertension in Malaysia needs additional attention. Strengthening the screening for hypertension in primary health-care settings in the high-risk groups and frequent health promotion to the community to enhance individual awareness and commitment to healthy living would be of immense value.

Arterial structure and function in vascular ageing: are you as old as your arteries?

Advancing age may be the most potent independent predictor of future cardiovascular events, a relationship that is not fully explained by time-related changes in traditional cardiovascular risk factors. Since some arteries exhibit differential susceptibility to atherosclerosis, generalisations regarding the impact of ageing in humans may be overly simplistic, whereas in vivo assessment of arterial function and health provide direct insight. Coronary and peripheral (conduit, resistance and skin) arteries demonstrate a gradual, age-related impairment in vascular function that is likely to be related to a reduction in endothelium-derived nitric oxide bioavailability and/or increased production of vasoconstrictors (e.g. endothelin-1). Increased exposure and impaired ability for defence mechanisms to resist oxidative stress and inflammation, but also cellular senescence processes, may contribute to age-related changes in vascular function and health. Arteries also undergo structural changes as they age. Gradual thickening of the arterial wall, changes in wall content (i.e. less elastin, advanced glycation end-products) and increase in conduit artery diameter are observed with older age and occur similarly in central and peripheral arteries. These changes in structure have important interactive effects on artery function, with increases in small and large arterial stiffness representing a characteristic change with older age. Importantly, direct measures of arterial function and structure predict future cardiovascular events, independent of age or other cardiovascular risk factors. Taken together, and given the differential susceptibility of arteries to atherosclerosis in humans, direct measurement of arterial function and health may help to distinguish between biological and chronological age-related change in arterial health in humans.

Mutation of Plekha7 attenuates salt-sensitive hypertension in the rat

PLEKHA7 (pleckstrin homology domain containing family A member 7) has been found in multiple studies as a candidate gene for human hypertension, yet functional data supporting this association are lacking. We investigated the contribution of this gene to the pathogenesis of salt-sensitive hypertension by mutating Plekha7 in the Dahl salt-sensitive (SS/JrHsdMcwi) rat using zinc-finger nuclease technology. After four weeks on an 8% NaCl diet, homozygous mutant rats had lower mean arterial (149 ± 9 mmHg vs. 178 ± 7 mmHg; P < 0.05) and systolic (180 ± 7 mmHg vs. 213 ± 8 mmHg; P < 0.05) blood pressure compared with WT littermates. Albumin and protein excretion rates were also significantly lower in mutant rats, demonstrating a renoprotective effect of the mutation. Total peripheral resistance and perivascular fibrosis in the heart and kidney were significantly reduced in Plekha7 mutant animals, suggesting a potential role of the vasculature in the attenuation of hypertension. Indeed, both flow-mediated dilation and endothelium-dependent vasodilation in response to acetylcholine were improved in isolated mesenteric resistance arteries of Plekha7 mutant rats compared with WT. These vascular improvements were correlated with changes in intracellular calcium handling, resulting in increased nitric oxide bioavailability in mutant vessels. Collectively, these data provide the first functional evidence that Plekha7 may contribute to blood pressure regulation and cardiovascular function through its effects on the vasculature.

Intramural location and size of arterial calcification are associated with stenosis at carotid bifurcation

PURPOSE

The purpose of this study was to investigate the association between internal carotid artery (ICA) stenosis and intramural location and size of calcification at the ICA origins and the origins of the cervical arteries proximal to the ICA.

METHOD

A total of 1139 ICAs were evaluated stenosis and calcification on the multi-detector row CT angiography. The intramural location was categorized into none, outside and inside location. The calcification size was evaluated on the 4-point grading scale. The multivariate analyses were adjusted for age, serum creatinine level, hypertension, hyperlipidemia, diabetes mellitus, smoking and alcohol habits.

RESULTS

Outside calcification at the ICA origins showed the highest multivariate odds ratio (OR) for the presence of ICA stenosis (30.0) and severe calcification (a semicircle or more of calcification at the arterial cross-sectional surfaces) did the second (14.3). In the subgroups of >70% ICA stenosis, the multivariate OR of outside location increased to 44.8 and that of severe calcification also increased to 32.7. Four of 5 calcified carotid plaque specimens extracted by carotid endarterectomy were histologically confirmed to be calcified burdens located outside the internal elastic lamia which were defined as arterial medial calcification.

CONCLUSIONS

ICA stenosis was strongly associated with severe calcification located mainly outside the carotid plaque. Outside calcification at the ICA origins should be evaluated separately from inside calcification, as a marker for the ICA stenosis. Additionally, we found that calcification at the origins of the cervical arteries proximal to the ICA was significantly associated with the ICA stenosis.

Quantification of regional differences in aortic stiffness in the aging human

There has been a growing awareness over the past decade that stiffening of the aorta, and its attendant effects on hemodynamics, is both an indicator and initiator of diverse cardiovascular, neurovascular, and renovascular diseases. Although different clinical metrics of arterial stiffness have been proposed and found useful in particular situations, there remains a need to understand better the complex interactions between evolving aortic stiffness and the hemodynamics. Computational fluid-solid-interaction (FSI) models are amongst the most promising means to understand such interactions for one can parametrically examine effects of regional variations in material properties and arterial geometry on local and systemic blood pressure and flow. Such models will not only increase our understanding, they will also serve as important steps towards the development of fluid-solid-growth (FSG) models that can further examine interactions between the evolving wall mechanics and hemodynamics that lead to arterial adaptations or disease progression over long periods. In this paper, we present a consistent quantification and comparison of regional nonlinear biaxial mechanical properties of the human aorta based on 19 data sets available in the literature and we calculate associated values of linearized stiffness over the cardiac cycle that are useful for initial large-scale FSI and FSG simulations. It is shown, however, that there is considerable variability amongst the available data and consequently that there is a pressing need for more standardized biaxial testing of the human aorta to collect data as a function of both location and age, particularly for young healthy individuals who serve as essential controls.

Calcification at orifices of aortic arch branches is a reliable and significant marker of stenosis at carotid bifurcation and intracranial arteries

PURPOSE

Simple rating scale for calcification in the cervical arteries and the aortic arch on multi-detector computed tomography angiography (MDCTA) was evaluated its reliability and validity. Additionally, we investigated where is the most representative location for evaluating the calcification risk of carotid bifurcation stenosis and atherosclerotic infarction in the overall cervical arteries covering from the aortic arch to the carotid bifurcation.

METHOD

The aortic arch and cervical arteries among 518 patients (292 men, 226 women) were evaluated the extent of calcification using a 4-point grading scale for MDCTA. Reliability, validity and the concomitant risk with vascular stenosis and atherosclerotic infarction were assessed.

RESULTS

Calcification was most frequently observed in the aortic arch itself, the orifices from the aortic arch, and the carotid bifurcation. Compared with the bilateral carotid bifurcations, the aortic arch itself had a stronger inter-observer agreement for the calcification score (Fleiss' kappa coefficients; 0.77), but weaker associations with stenosis and atherosclerotic infarction. Calcification at the orifices of the aortic arch branches had a stronger inter-observer agreement (0.74) and enough associations with carotid bifurcation stenosis and intracranial stenosis. In addition, the extensive calcification at the orifices from the aortic arch was significantly associated with atherosclerotic infarction, similar to the calcification at the bilateral carotid bifurcations.

CONCLUSIONS

The orifices of the aortic arch branches were the novel representative location of the aortic arch and overall cervical arteries for evaluating the calcification extent. Thus, calcification at the aortic arch should be evaluated with focus on the orifices of 3 main branches.

Machine learning techniques for arterial pressure waveform analysis

The Arterial Pressure Waveform (APW) can provide essential information about arterial wall integrity and arterial stiffness. Most of APW analysis frameworks individually process each hemodynamic parameter and do not evaluate inter-dependencies in the overall pulse morphology. The key contribution of this work is the use of machine learning algorithms to deal with vectorized features extracted from APW. With this purpose, we follow a five-step evaluation methodology: (1) a custom-designed, non-invasive, electromechanical device was used in the data collection from 50 subjects; (2) the acquired position and amplitude of onset, Systolic Peak (SP), Point of Inflection (Pi) and Dicrotic Wave (DW) were used for the computation of some morphological attributes; (3) pre-processing work on the datasets was performed in order to reduce the number of input features and increase the model accuracy by selecting the most relevant ones; (4) classification of the dataset was carried out using four different machine learning algorithms: Random Forest, BayesNet (probabilistic), J48 (decision tree) and RIPPER (rule-based induction); and (5) we evaluate the trained models, using the majority-voting system, comparatively to the respective calculated Augmentation Index (AIx). Classification algorithms have been proved to be efficient, in particular Random Forest has shown good accuracy (96.95%) and high area under the curve (AUC) of a Receiver Operating Characteristic (ROC) curve (0.961). Finally, during validation tests, a correlation between high risk labels, retrieved from the multi-parametric approach, and positive AIx values was verified. This approach gives allowance for designing new hemodynamic morphology vectors and techniques for multiple APW analysis, thus improving the arterial pulse understanding, especially when compared to traditional single-parameter analysis, where the failure in one parameter measurement component, such as Pi, can jeopardize the whole evaluation.

The effects of whey protein on cardiometabolic risk factors

Obesity has reached epidemic proportions worldwide. The health consequences of obesity are more dangerous when associated with the metabolic syndrome and its components. Studies show that whey protein and its bioactive components can promote greater benefits compared to other protein sources such as egg and casein. The aim of this paper is to review the effects of whey protein on cardiometabolic risk factors. Using PubMed as the database, a review was conducted to identify current scientific literature on whey protein and the components of the metabolic syndrome published between 1970 and 2012. Consumption of whey protein seems to play an anti-obesity and muscle-protective role during dieting by increasing thermogenesis and maintaining lean mass. In addition, whey protein has been shown to improve glucose levels and insulin response, promote a reduction in blood pressure and arterial stiffness, and improve lipid profile. The collective view of current scientific literature indicates that the consumption of whey protein may have beneficial effects on some symptoms of the metabolic syndrome as well as a reduction in cardiovascular risk factors.

Azelnidipine plus olmesartan versus amlodipine plus olmesartan on arterial stiffness and cardiac function in hypertensive patients: a randomized trial

Purpose

To compare the long-term effects of olmesartan combined with either azelnidipine or amlodipine on central blood pressure (CBP), left ventricular (LV) mass index (LVMI), LV diastolic function (e′ velocity, E/e′ ratio, E/A ratio) and arterial stiffness (brachial-ankle pulse wave velocity [baPWV] and augmentation index normalized for a heart rate of 75 bpm [AIx]).

Patients and methods

Patients with systolic BP ≥ 140 mmHg and/or diastolic BP ≥ 90 mmHg received olmesartan monotherapy (20 mg/day) for 12 weeks. They were then randomly assigned to fixed-dose add-on therapy with azelnidipine (16 mg/day; n = 26) or amlodipine (5 mg/day; n = 26) for a further 2 years. CBP, LVMI, e′ velocity, E/e′ ratio, E/A ratio, baPWV, and AIx were measured at baseline, 6 months, and 2 years.

Results

Baseline characteristics of both groups were similar. The decrease in brachial BP over 2 years was similar in both groups. CBP, LVMI, E/e′ ratio, baPWV, and AIx decreased significantly, and the E/A ratio and e′ velocity increased significantly in both groups. The decreases in CBP (P < 0.001), AIx (P < 0.001), baPWV (P < 0.001), LVMI (P < 0.001), and E/e′ (P = 0.002) as well as the increase in E/A ratio (P = 0.03) over 2 years were significantly greater in the olmesartan/azelnidipine group than in the olmesartan/amlodipine group. Multivariate linear regression analyses showed that the changes in baPWV (β = 0.41, P < 0.001) and CBP (β = 0.47, P = 0.01) were independently associated with the change in LVMI, the change in baPWV (β = 0.25, P < 0.001) was independently associated with the change in E/e′ ratio, and the changes in baPWV (β = 0.21, P = 0.001) and AIx (β = 0.25, P = 0.03) were independently associated with the change in E/A ratio.

Conclusion

Treatment with olmesartan/azelnidipine for 2 years resulted in greater improvements in CBP, LVMI, and LV diastolic function, and arterial stiffness compared with olmesartan/amlodipine. Improvements in LV diastolic function were associated with improvements in arterial stiffness.

Association of arterial stiffness with obesity in Australian women: a pilot study

This study investigated the arterial stiffness status in overweight/obese Australian women compared with their lean counterparts. Twenty-six Caucasian women were designated into one of two groups: overweight/obese (body mass index [BMI] 25-34.9 kg/m2 [ n=12]) and lean (BMI 18.5-24.9 kg/m2 [n=14]) groups. Participants were assessed for clinical, anthropometric, metabolic, and augmentation index (AIx) measurements. Age was similar between groups (P=.482). BMI was significantly higher in overweight/obese compared with lean participants (30.26±1.09 vs 21.62±0.52 kg/m2, P=.001) as well as the percentage of body fat (40.60±2.43 vs 21.57±1.13, P=.001), waist circumference (91.47±2.77 vs 70.67±1.60, P=.001), and waist/hip ratio (0.81±0.04 vs 0.71±0.03, P=.036). Overweight/obese group showed higher total cholesterol, triglyceride, low-density lipoprotein cholesterol, and fasting glucose levels compared with the lean group (all P<.05). Both systolic (122.92±3.18 mm Hg vs 108.14±2.42 mm Hg, P=.001) and diastolic (83.58±2.43 mm Hg vs 72.43±1.29 mm Hg, P=.0001) blood pressures, as well as AIx (50.08±4.7 vs 120.79±2.17, P=.001) were significantly higher in the overweight/obese group compared with the lean group. AIx was positively associated with measurements of body composition (P<.05), triglycerides (r=0.361, P=.035) and glucose levels (r=0.371, P=.031), and systolic and diastolic blood pressure (r=0.793 and r=0.718, respectively; P=.0001). This data suggests that arterial stiffness is associated with obesity, along with other metabolic abnormalities in Australian women.

How to integrate multiple comorbidities in guideline development: article 10 in Integrating and coordinating efforts in COPD guideline development. An official ATS/ERS workshop report

BACKGROUND

Professional societies, like many other organizations around the world, have recognized the need to use more rigorous processes to ensure that health care recommendations are informed by the best available research evidence. This is the 10th of a series of 14 articles that were prepared to advise guideline developers in respiratory and other diseases. This article deals with how multiple comorbidities (co-existing chronic conditions) may be more effectively integrated into guidelines.

METHODS

In this review we addressed the following topics and questions using chronic obstructive pulmonary disease (COPD) as an example. (1) How important are multiple comorbidities for guidelines? (2) How have other organizations involved in the development of guidelines for single chronic disease approached the problem of multiple comorbidities? (3) What are the implications of multiple comorbidities for pharmacological treatment? (4) What are the potential changes induced by multiple comorbidities in guidelines? (5) What are the implications of considering a population of older patients with multiple comorbidities in designing clinical trials? Our conclusions are based on available evidence from the published literature, experience from guideline developers, and workshop discussions. We did not attempt to examine all Clinical Practice Guidelines (CPGs) and relevant literature. Instead, we selected CPGs generated by prominent professional organizations and relevant literature published in widely read journals, which are likely to have a high impact on clinical practice.

RESULTS AND CONCLUSIONS

A widening gap exists between the reality of the care of patients with multiple chronic conditions and the practical clinical recommendations driven by CPGs focused on a single disease, such as COPD. Guideline development panels should aim for multidisciplinary representation, especially when contemplating recommendations for individuals aged 65 years or older (who often have multiple comorbidities), and should evaluate the quality of evidence and the strength of recommendations targeted at this population. A priority area for research should be to assess the effect of multiple concomitant medications and assess how their combined effects are altered by genetic, physiological, disease-related, and other factors. One step that should be implemented immediately would be for existing COPD guidelines to add new sections to address the impact of multiple comorbidities on screening, diagnosis, prevention, and management recommendations. Research should focus on the possible interaction of multiple medications. Furthermore, genetic, physiological, disease-related, and other factors that may influence the directness (applicability) of the evidence for the target population in clinical practice guidelines should be examined.

Effects of psyllium on metabolic syndrome risk factors

High-fibre intake has been shown to reduce the risk of metabolic syndrome (MS), cardiovascular disease and type 2 diabetes. Psyllium is one of the most widely used fibre supplements because it is reasonably cheap and is better tolerated than other fibre supplements. The review of the literature supports the notion that the consumption of psyllium provides benefits to many components of the MS. Psyllium supplementation does improve glucose levels and insulin response, blood pressure, as well as lipid profile in both animals and humans, thereby reducing metabolic risk factors. Appetite has also been reported to decrease after the consumption of psyllium in most studies. Collectively, psyllium supplementation could be promoted to patients who present MS risk factors, such as hypercholesterolaemia, hypertriglyceridaemia and hyperglycaemia. It may also play a role in controlling body weight, body composition, appetite and hypertension, but further investigation is still required.

Arterial stiffness is associated with carotid atherosclerosis in hypertensive patients (the Campania Salute Network)

BACKGROUND

Pulse pressure/stroke volume indexed to height(2.04) (PP/SVi) is a validated measure of arterial stiffness, but its relation to carotid atherosclerosis is unknown.

METHODS

Clinical, echocardiographic, and carotid ultrasound data from 6,209 hypertensive patients without prevalent cardiovascular (CV) disease in the Campania Salute Network were analyzed. The population was grouped into tertiles of PP/SVi. From carotid ultrasound, peak and mean intima-media thickness (IMT) and presence of carotid plaques in the common and internal carotid arteries were reported.

RESULTS

Increasing PP/SVi tertile was associated with a parallel increase in age, blood pressure, total serum cholesterol and the number of antihypertensive drugs used (all P < 0.01). Higher PP/SVi was also associated with greater peak and mean IMT (all P < 0.01), also when adjusting for age, gender, blood pressure, lipid profile, and diabetes mellitus (all P < 0.01). Similarly, compared to the lower PP/SVi tertile, the multiple adjusted prevalence ratio of carotid plaque was 7 (95% confidence interval (CI) 1-13, P < 0.03) in the middle tertile and 21 (95% CI 15-28, P < 0.0001) in the upper tertile, independently of confounders.

CONCLUSION

In treated hypertensive patients participating in the Campania Salute Network, higher PP/SVi is associated with carotid atherosclerosis independent of well-known clinical confounders.

Role of dietary therapies in the prevention and treatment of hypertension

Blood pressure naturally rises with increasing age. The rate of change in blood pressure with age is regulated in part by genetic factors, but can also be altered through sustained dietary modification. Dietary approaches to modify blood pressure remain an important part of cardiovascular health promotion, which is especially important given the aging of the general population coupled with the increasing prevalence of obesity and metabolic disturbances. Specific modification of dietary components such as macronutrients and micronutrients could be helpful to lower blood pressure and alter the slope of blood pressure change whereas nutritional supplements are less likely to have a substantial beneficial effect. Population-wide generalizations regarding diet are impractical as individualized strategies are more likely to be successful in facilitating long-term benefits in improving blood-pressure control. Consequently, more effort needs to be focused on evaluating data from large-scale observational and interventional studies and interpreting their information in a clinically relevant manner, which is likely to be helpful for individual patients. Providing education on the relationship between diet and blood pressure from an early age is most likely to produce tangible benefits.

Genome-wide association study identifies six new loci influencing pulse pressure and mean arterial pressure

Numerous genetic loci have been associated with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in Europeans. We now report genome-wide association studies of pulse pressure (PP) and mean arterial pressure (MAP). In discovery (N = 74,064) and follow-up studies (N = 48,607), we identified at genome-wide significance (P = 2.7 × 10(-8) to P = 2.3 × 10(-13)) four new PP loci (at 4q12 near CHIC2, 7q22.3 near PIK3CG, 8q24.12 in NOV and 11q24.3 near ADAMTS8), two new MAP loci (3p21.31 in MAP4 and 10q25.3 near ADRB1) and one locus associated with both of these traits (2q24.3 near FIGN) that has also recently been associated with SBP in east Asians. For three of the new PP loci, the estimated effect for SBP was opposite of that for DBP, in contrast to the majority of common SBP- and DBP-associated variants, which show concordant effects on both traits. These findings suggest new genetic pathways underlying blood pressure variation, some of which may differentially influence SBP and DBP.