Is augmentation index a good measure of vascular stiffness in the elderly?

Maternal vascular-placental axis in the third trimester in women with gestational diabetes mellitus, hypertensive disorders, and unaffected pregnancies

BACKGROUND

Hypertensive disorders of pregnancy and gestational diabetes mellitus are characterized by vascular dysfunction and are associated with long term cardiovascular risks.

OBJECTIVE

This study aimed to compare different markers of maternal vascular function in women with gestational diabetes mellitus, preeclampsia, or gestational hypertension and in women whose pregnancies were unaffected by these complications and to assess the association between maternal vascular function and markers of placental perfusion and maternal vascular-placental axis in 4 groups of women.

STUDY DESIGN

This was a prospective observational study of women who had routine hospital visits at 35 0/7 to 36 6/7 weeks of gestation at King's College Hospital, London, United Kingdom. The routine hospital visit included recording of maternal demographic characteristics and medical history, ultrasound examination for fetal anatomy and growth, Doppler studies of the uterine arteries and ophthalmic arteries, carotid-femoral pulse wave velocity measurements, estimation of the augmentation index and total peripheral resistance, and measurements of serum placental growth factor and soluble fms-like tyrosine kinase 1. Linear regression analysis was performed for the outcomes of uterine artery pulsatility index multiple of the median, placental growth factor multiple of the median, and soluble fms-like tyrosine kinase 1 multiple of the median. The ophthalmic artery peak systolic velocity ratio, pulse wave velocity, augmentation index, and total peripheral vascular resistance were assessed as potential predictors. This analysis was performed on all women and separately in the different groups.

RESULTS

The study population of 6502 women included 614 (9.4%) with gestational diabetes mellitus, 140 (2.1%) who subsequently developed preeclampsia, and 129 (2.0%) who developed gestational hypertension. Women with gestational diabetes mellitus had increased pulse wave velocity compared with those with pregnancies unaffected by gestational diabetes mellitus, preeclampsia, or gestational hypertension. Women with preeclampsia or gestational hypertension had lower placental growth factor multiple of the median and higher uterine artery pulsatility index multiple of the median, soluble fms-like tyrosine kinase 1 multiple of the median, augmentation index, pulse wave velocity, total peripheral resistance, and ophthalmic artery peak systolic velocity ratio than those with unaffected pregnancies. In women with unaffected pregnancies, the ophthalmic artery peak systolic velocity ratio was predictive of the uterine artery pulsatility index multiple of the median, and ophthalmic artery peak systolic velocity ratio, augmentation index, total peripheral resistance, and pulse wave velocity were predictive of the placental growth factor multiple of the median and the soluble fms-like tyrosine kinase 1 multiple of the median. In women with gestational diabetes mellitus, the ophthalmic artery peak systolic velocity ratio was predictive of the uterine artery pulsatility index multiple of the median; the ophthalmic artery peak systolic velocity ratio, total peripheral resistance, and pulse wave velocity were predictive of the placental growth factor multiple of the median; and total peripheral resistance was predictive of the soluble fms-like tyrosine kinase 1 multiple of the median. In women with preeclampsia, the ophthalmic artery peak systolic velocity ratio was predictive of the uterine artery pulsatility index multiple of the median, placental growth factor multiple of the median, and soluble fms-like tyrosine kinase 1 multiple of the median. In women unaffected by gestational diabetes mellitus, preeclampsia, or gestational hypertension, the ophthalmic artery peak systolic velocity ratio was predictive of the uterine artery pulsatility index multiple of the median, and the augmentation index, total peripheral resistance, pulse wave velocity, and the ophthalmic artery peak systolic velocity ratio were predictive of the placental growth factor multiple of the median and the soluble fms-like tyrosine kinase 1 multiple of the median.

CONCLUSION

In the third trimester of pregnancy, women with preeclampsia, gestational hypertension, and gestational diabetes mellitus present with increased arterial stiffness. In addition, women diagnosed with hypertensive complications showed increased peripheral vascular resistance. The ophthalmic artery peak systolic velocity ratio provided predictive information for placental perfusion and function in all pregnant women, whereas vascular indices were more informative for placental function in women with unaffected pregnancies and those with gestational diabetes mellitus than in those with preeclampsia or gestational hypertension. Our data suggest that vascular assessment in women during pregnancy not only may provide information about maternal vascular health but also can be used to provide information about individual risk factors for placental insufficiency. The selection of the vascular index will have to be tailored according to the maternal profile and pregnancy complication.

Early and Late Effects of Medium Cutoff Dialyzer on Arterial Stiffness in Maintenance Hemodialysis Patients

INTRODUCTION

Removing uremic toxins from the body is one of the most critical points in the maintenance hemodialysis (MHD) population. This study aimed to evaluate the effects of medium cutoff (MCO) membranes on pulse wave velocity (PWV) and augmentation index (AIx), early markers of arterial stiffness, in MHD patients over both short- and long-term periods.

METHODS

Twenty MHD patients were included in this study. Patients were switched from low-flux to MCO membranes. Hemodynamic parameters and laboratory results were recorded in the low-flux membrane as baseline and the second week and the sixth month after switching to the MCO membranes. PWV and AIx were measured using the IME Mobil-O-Graph.

FINDINGS

The median was 69.5 years old, with 60% female predominance. 35% of the patients were diabetic, 70% had hypertension, and 21.1% were smokers. The median systolic, diastolic blood pressure, mean arterial pressure, and pulse were similar at all study time points. The pulse pressure tended to decrease with a significant reduction in the sixth month (p = 0.73 and p = 0.03). We did not observe any significant differences regarding the PWV measurements (p = 0.71 and p = 0.62) and total vascular resistance (p = 0.23 and p = 0.79). The median AIx decreased during the study time points, with a significant difference between the second-week MCO and the sixth-month MCO measurements (p = 0.04).

DISCUSSION

Our findings underscore the potential benefits of MCO membranes to provide a favorable cardiovascular profile in conventional HD setting.

A systematic review of the accuracy of prognostic tests and scoring systems for use in the Global Vascular Guidelines' PLAN concept for the treatment of chronic limb threatening ischemia

OBJECTIVE

The 2019 Global Vascular Guidelines recommend risk assessment for evidence based revascularization based on the acronym PLAN: Patient risk, Limb severity and ANatomical complexity of disease. This meta-analysis compares a multitude of prognostic tests within these categories.

METHODS

A systematic review and meta-analysis of tests that estimated 1-year major event (amputation-free survival and major adverse limb events) probability. Individual patient data were reconstructed from survival estimate curves. With presence or absence of major events, sensitivity, specificity, and area under receiver operating characteristics curves (AUC) were computed. Tests with an AUC ≥70%, or that correlated with revascularization feasibility were included. Practical application of tests was assessed to make a recommendation on PLAN implementation.

RESULTS

Ninety-six studies describing 77 unique predictive techniques were included, of which thirteen were sufficient. These 13 tests were divided in four Patient risk (5 studies), three Limb severity (3 studies), and six ANatomical complexity of disease (9 studies). Patient risk: Three tests were included: biochemical assessment of calprotectin and C-reactive protein, radiologic measurement of sarcopenia, and predictive score with the GermanVasc chronic limb-threatening ischemia (CLTI) score. These tests scored AUCs of 82.0%, 72.7%, and 71.8%, respectively, of which the GermanVasc CLTI score was deemed most applicable in clinical practice. Limb severity: The adjusted Wound Ischemia foot Infection score (WIfI) resulted as best predictive score (AUC, 78.8%), but due to the lack of external validation, the original WIfI score was deemed best applicable. ANatomical complexity of disease: No test surpassed 70% AUC for 1-year event estimation, and was correlated with feasibility of revascularization, the latter only being served by the Global Limb Anatomic Staging System.

CONCLUSIONS

In evidence-based revascularization in patients with CLTI according to the PLAN concept, we recommend to use GermanVasc, WIfI, and the Global Limb Anatomic Staging System.

Maternal vascular dysfunction in gestational diabetes is associated with birth of small neonates

AIMS

The study aimed to evaluate maternal hemodynamic and vascular changes in women with small-for-gestational age(SGA) and large-for-gestational age(LGA) fetuses in the presence and absence of gestational diabetes mellitus(GDM).

MATERIALS

Women at 35+0 to 36+6 weeks' gestation with and without GDM were included. Maternal demographics, ultrasound for fetal growth, Doppler studies of uterine and ophthalmic arteries, carotid-femoral pulse-wave velocity(PWV), augmentation index, cardiac output, and total peripheral resistance(TPR) were recorded. Multinomial logistic regression was used.

RESULTS

Of 11,132 women, 1,228(11.0%) developed GDM. In GDM pregnancies, 158(12.8%) delivered SGA and 136(11.1%) delivered LGA neonates, while non-GDM pregnancies had 1,051(10.6%) SGA and 806(8.1%) LGA neonates. In GDM and non-GDM women, SGA groups had the highest uterine artery pulsatility index(PI) percentiles, PWV and ophthalmic artery peak systolic velocity ratio. PWV was higher in the GDM SGA group compared to non-GDM SGA group. Cardiac output was lower in SGA groups when compared to the AGA group. In women with GDM, TPR, ophthalmic artery PSV ratio and uterine artery PI percentile had a positive association with the development of SGA.

CONCLUSIONS

Women with GDM and vascular dysfunction have higher risk to deliver SGA neonates. Maternal hemodynamic and vascular maladaptation could potentially explain the development of SGA in women with GDM.

Analysis of the Sex-Specific Risk Factors for Arterial Stiffness

Background

To explore the sex-specific risk factors of associated with arterial stiffness.

Methods

A total of 28,291 participants from the Kailuan study cohort were enrolled in this study. A multivariate linear regression analysis and a multivariate logistic regression model were used to analyze the influencing factors of arteriosclerosis (indexed using the brachial-ankle pulse wave velocity, baPWV) between different sexes.

Results

The incidence of arteriosclerosis (baPWV greater than or equal to 1400 cm/s) was 54.70%. The incidence of arteriosclerosis in males (62.13%) was higher than in females (37.41%) (p < 0.01). According to age stratification (5 years difference for each group), the baPWV values of males in all age groups <70 years were higher than in females (p < 0.01). The increase in baPWV values was higher in females over 45 years than in males and correlated with males in the 70-75 age group. The multivariate linear regression model showed that for every 5-year increase in age, the baPWV increased by 62.55 cm/s in males and 71.86 cm/s in females. Furthermore, for every 10 mmHg increase in systolic blood pressure (SBP), the baPWV increased by 61.01 cm/s in males and 51.86 cm/s in females. Regular physical exercise reduced the baPWV in males, but there was no statistical correlation in females. The waist-to-hip ratio (WHR) increased the baPWV in females yet was not statistically significant in males. Multivariate logistic regression analysis showed that after adjusting for confounding factors (age, WHR, SBP, heart rate, triglyceride, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), high-sensitivity C-reactive protein (hs-CRP), estimated glomerular filtration rate (eGFR), diabetes, higher education, higher income, smoking, drinking, and physical exercise), males were 1.89 times more likely than females to develop arteriosclerosis (p < 0.05). A stratified analysis of males and females showed that the risk of arteriosclerosis was higher in females than in males in the 45-60 and over 60 age groups compared with those in the under 44 age group (p < 0.01). Diabetes, LDL-C, and hs-CRP were more likely to be correlated with arteriosclerosis in females than in males (odds ratio (OR): 2.32, 1.26, 1.08 vs. 1.83, 1.17, 1.02, respectively, p < 0.05). Higher education levels reduced the risk of arteriosclerosis in males and females, with OR values of 0.64 and 0.84, respectively (p < 0.05).

Conclusions

The arteriosclerosis detection rate in males was higher than in females. Conversely, the increase in baPWV in females older than 45 years was higher than in males. Meanwhile, WHR, diabetes, LDL-C, and hs-CRP were more likely to be correlated with arteriosclerosis in females.

Clinical Trial Registration

Chinese Clinical Trail Registry, URL: https://www.chictr.org.cn/showproj.html?proj=8050. Unique identifier: ChiCTR-TNRC-11001489 .

Advancing prediction of age-related vascular cognitive impairment based on peripheral and retinal vascular health in a pilot study: a novel comprehensive assessment developed for a prospective workplace-based cohort (The Semmelweis Study)

With a growing elderly population in the European Union, age-related diseases associated with unhealthy aging pose increasing public health challenges, including a loss of independence and heightened societal burdens. The Semmelweis Study, a prospective occupational cohort study in Hungary, seeks to identify determinants of unhealthy aging, focusing on the complex relationship between lifestyle, environmental, occupational factors, and the development of chronic age-associated diseases, including age-related vascular cognitive impairment (VCI). The primary objective of this pilot study was to establish a robust, high-throughput assessment methodology to comprehensively evaluate both peripheral and cerebrovascular health to provide a solid foundation for the forthcoming Semmelweis Study framework. The study involved 49 participants aged 23 to 87 years, and it assessed multi-domain cognitive performance through an automated battery of tests (CANTAB). Vascular health was comprehensively evaluated using laser speckle contrast imaging (LSCI), flow-mediated dilation (FMD), static and dynamic retinal vessel analysis (SVA, DVA), and measurements of vascular stiffness. The retinal microvasculature, which closely mirrors the cerebral circulation in anatomy, physiology, and pathophysiology, provided a unique window for examination. Optical imaging through SVA and DVA enables the identification of structural and functional changes in the central nervous system's microcirculation, which are highly relevant to the pathogenesis of VCI. Subsequently, the collected measures were integrated into vascular health indices using principal component analysis (PCA) and the relationship to the age and cognitive status of study participants was explored. These comprehensive vascular health indices demonstrated a correlation not only with age but also with cognitive performance. This methodology holds promise for providing novel insights into the intricate interplay between vascular and cognitive health within the context of the Semmelweis Study.

Characterization of intracranial compliance in healthy subjects using a noninvasive method - results from a multicenter prospective observational study

PURPOSE

An FDA-approved non-invasive intracranial pressure (ICP) monitoring system enables the assessment of ICP waveforms by revealing and analyzing their morphological variations and parameters associated with intracranial compliance, such as the P2/P1 ratio and time-to-peak (TTP). The aim of this study is to characterize intracranial compliance in healthy volunteers across different age groups.

METHODS

Healthy participants, both sexes, aged from 9 to 74 years old were monitored for 5 min in the supine position at 0º. Age was stratified into 4 groups: children (≤ 7 years); young adults (18 ≤ age ≤ 44 years); middle-aged adults (45 ≤ age ≤ 64 years); older adults (≥ 65 years). The data obtained was the non-invasive ICP waveform, P2/P1 ratio and TTP.

RESULTS

From December 2020 to February 2023, 188 volunteers were assessed, of whom 104 were male, with a median (interquartile range) age of 41 (29-51), and a median (interquartile range) body mass index of 25.09 (22.57-28.04). Men exhibited lower values compared to women for both the P2/P1 ratio and TTP (p < 0.001). There was a relative rise in both P2/P1 and TTP as age increased (p < 0.001).

CONCLUSIONS

The study revealed that the P2/P1 ratio and TTP are influenced by age and sex in healthy individuals, with men displaying lower values than women, and both ratios increasing with age. These findings suggest potential avenues for further research with larger and more diverse samples to establish reference values for comparison in various health conditions.

TRIAL REGISTRATION

Brazilian Registry of Clinical Trials (RBR-9nv2h42), retrospectively registered 05/24/2022. UTN: U1111-1266-8006.

Ambulatory blood pressure parameters and their association with albuminuria in adolescents with type 1 diabetes mellitus

BACKGROUND

This study aimed to evaluate the blood pressure (BP) status, including arterial stiffness parameters, hemodynamic indicators, circadian profile, and its association with albuminuria in adolescents with type 1 diabetes mellitus (DM1).

METHODS

The analysis included 46 patients, with diabetes duration of 7.38 ± 3.48 years. Ambulatory blood pressure monitoring (ABPM) was conducted using an oscillometric device, the Mobil-O-Graph, which is a Pulse Wave Analysis Monitor.

RESULTS

Hypertension (HT) was diagnosed in 31 adolescents (67% of patients), primarily due to isolated nocturnal BP (21 cases, 68% of HT cases). The HT group exhibited significantly increased diastolic load (DL). Pulse wave velocity (PWV, a measure of arterial stiffness) values showed a strong correlation with both peripheral systolic BP (r = 0.954) and central systolic BP (r = 0.838). Additionally, non-dipping status was found in 61% of the HT group. Urinary albumin excretion (UAE) was positively correlated with diastolic BP (particularly nocturnal) peripheral and central BP, DL, heart rate, augmentation index (AIx@75), and nocturnal total vascular resistance (TVR). Diastolic non-dippers exhibited a significant increase in UAE.

CONCLUSIONS

Hypertension is a common complication in adolescents with type 1 diabetes mellitus, primarily caused by elevated nocturnal diastolic BP. Albuminuria is mainly associated with diastolic BP, especially during the nocturnal period and in cases of diastolic non-dipping status. The association of UAE with AIx@75 and nocturnal TVR suggests the presence of early-stage vascular disease in diabetic adolescents.

Arterial stiffness and cardiovascular risk in patients with nephrolithiasis: a 10-year prospective study

BACKGROUND

Nephrolithiasis is frequently associated with cardiovascular diseases. These conditions present common risk factors: systemic inflammation that promotes oxidative stress leading to arterial wall stiffening may also play a role in plaque formation predisposing to nephrolithiasis.

OBJECTIVES

The aim of this study was to evaluate arterial stiffness indices at baseline and after a 10-year follow-up, in patients with nephrolithiasis compared with patients without.

METHODS

A total of 82 patients (37 men; mean age 45 ± 13 years) were enrolled at the Geriatrics and Nephrology Outpatient Clinic: 66 were diagnosed with nephrolithiasis, whereas the control group consisted of 16 individuals. At baseline and after 10 years, they underwent clinical evaluation and arterial stiffness measurement, such as carotid-femoral pulse wave velocity (CF-PWV), by arterial applanation tonometry.

RESULTS

At baseline, when compared with the control group, patients with nephrolithiasis showed higher SBP and CF-PWV. After 10 years, patients with nephrolithiasis, but not those without, showed a significant raise in CF-PWV, even after adjustment for age and sex. In a stepwise regression model, with CF-PWV changes during the follow-up as the dependent variable, and age, sex, follow-up years, Δ mean arterial pressure, BMI, hypertension and nephrolithiasis as independent variables, nephrolithiasis was proved to be the only significant predictor of ΔCF-PWV, accounting for 6% of the variance.

CONCLUSION

Our study shows higher baseline CF-PWV and greater increase in ΔCF-PWV within 10 years in individuals with nephrolithiasis than in those without, demonstrating an increased cardiovascular risk for nephrolithiasis patients.

Plasma Metabolome Predicts Aortic Stiffness and Future Risk of Coronary Artery Disease and Mortality After 23 Years of Follow-Up in the General Population

BACKGROUND

Increased aortic stiffness (arteriosclerosis) is associated with early vascular aging independent of age and sex. The underlying mechanisms of early vascular aging remain largely unexplored in the general population. We aimed to investigate the plasma metabolomic profile in aortic stiffness (vascular aging) and associated risk of incident cardiovascular disease and mortality.

METHODS AND RESULTS

We included 6865 individuals from 2 Swedish population-based cohorts. Untargeted plasma metabolomics was performed by liquid-chromatography mass spectrometry. Aortic stiffness was assessed directly by carotid-femoral pulse wave velocity (PWV) and indirectly by augmentation index (AIx@75). A least absolute shrinkage and selection operator (LASSO) regression model was created on plasma metabolites in order to predict aortic stiffness. Associations between metabolite-predicted aortic stiffness and risk of new-onset cardiovascular disease, cardiovascular mortality, and all-cause mortality were calculated. Metabolite-predicted aortic stiffness (PWV and AIx@75) was positively associated particularly with acylcarnitines, dimethylguanidino valeric acid, glutamate, and cystine. The plasma metabolome predicted aortic stiffness (PWV and AIx@75) with good accuracy (R2=0.27 and R2=0.39, respectively). Metabolite-predicted aortic stiffness (PWV and AIx@75) was significantly correlated with age, sex, systolic blood pressure, body mass index, and low-density lipoprotein. After 23 years of follow-up, metabolite-predicted aortic stiffness (PWV and AIx@75) was significantly associated with increased risk of new-onset coronary artery disease, cardiovascular mortality, and all-cause mortality.

CONCLUSIONS

Aortic stiffness is associated particularly with altered metabolism of acylcarnitines, cystine, and dimethylguanidino valeric acid. These metabolic disturbances predict increased risk of new-onset coronary artery disease, cardiovascular mortality, and all-cause mortality after more than 23 years of follow-up in the general population.

Arterial stiffness tested by pulse wave velocity and augmentation index for cardiovascular risk stratification in antiphospholipid syndrome

OBJECTIVES

Cardiovascular disease is a major cause of morbidity and mortality in Antiphospholipid syndrome (APS). Arterial stiffness (ArS) has emerged as a predictor of future cardiovascular events in the general population. We aimed to assess ArS in patients with thrombotic APS versus diabetes mellitus (DM) and healthy controls (HC) and identify predictors of increased ArS in APS.

METHODS

ArS was evaluated by carotid-femoral pulse wave velocity (cfPWV) and augmentation index normalized to 75 beats/min (AIx@75) using the SphygmoCor device. Participants also underwent carotid/femoral ultrasound for atherosclerotic plaque detection. We used linear regression to compare ArS measures among groups and assess ArS determinants in the APS group.

RESULTS

We included 110 patients with APS (70.9% female, mean age 45.4 years), 110 DM patients and 110 HC, all age/sex matched. After adjustment for age, sex, cardiovascular risk factors and plaque presence, APS patients exhibited similar cfPWV [β = -0.142 (95% CI -0.514, 0.230), p = 0.454] but increased AIx@75 [β = 4.525 (95% CI 1.372, 7.677), p = 0.005] compared with HC and lower cfPWV (p < 0.001) but similar AIx@75 (p = 0.193) versus DM patients. In the APS group, cfPWV was independently associated with age [β = 0.056 (95% CI 0.034, 0.078), p < 0.001], mean arterial pressure (MAP) [β = 0.070 (95% CI 0.043, 0.097), p < 0.001], atherosclerotic femoral plaques [β = 0.732 (95% CI 0.053, 1.411), p = 0.035] and anti-β2-glycoprotein I IgM positivity [β = 0.696 (95% CI 0.201, 1.191), p = 0.006]. AIx@75 was associated with age [β = 0.334 (95% CI 0.117, 0.551), p = 0.003], female sex [β = 7.447 (95% CI 2.312, 12.581), p = 0.005] and MAP [β = 0.425 (95% CI 0.187, 0.663), p = 0.001].

CONCLUSION

APS patients exhibit elevated AIx@75 vs HC and similar to DM patients, indicating enhanced arterial stiffening in APS. Given its prognostic value, ArS evaluation may help to improve cardiovascular risk stratification in APS.

An in silico study of the effects of cardiovascular aging on carotid flow waveforms and indexes in a virtual population

Cardiovascular aging is strongly associated with increased risk of cardiovascular disease and mortality. Moreover, health and lifestyle factors may accelerate age-induced alterations, such as increased arterial stiffness and wall dilation, beyond chronological age, making the clinical assessment of cardiovascular aging an important prompt for preventative action. Carotid flow waveforms contain information about age-dependent cardiovascular properties, and their ease of measurement via noninvasive Doppler ultrasound (US) makes their analysis a promising tool for the routine assessment of cardiovascular aging. In this work, the impact of different aging processes on carotid waveform morphology and derived indexes is studied in silico, with the aim of establishing the clinical potential of a carotid US-based assessment of cardiovascular aging. One-dimensional (1-D) hemodynamic modeling was employed to generate an age-specific virtual population (VP) of N = 5,160 realistic carotid hemodynamic waveforms. The resulting VP was statistically validated against in vivo aging trends in waveforms and indexes from the literature, and simulated waveforms were studied in relation to age and underlying cardiovascular parameters. In our study, the carotid flow augmentation index (FAI) significantly increased with age (with a median increase of 50% from the youngest to the oldest age group) and was strongly correlated to local arterial stiffening (r = 0.94). The carotid pulsatility index (PI), which showed less pronounced age variation, was inversely correlated with the reflection coefficient at the carotid branching (r = -0.88) and directly correlated with carotid net forward wave energy (r = 0.90), corroborating previous literature where it was linked to increased risk of cerebrovascular damage in the elderly. There was a high correlation between corrected carotid flow time (ccFT) and cardiac output (CO) (r = 0.99), which was not affected by vascular age. This study highlights the potential of carotid waveforms as a valuable tool for the assessment of cardiovascular aging.NEW & NOTEWORTHY An age-specific virtual population was generated based on a 1-D model of the arterial circulation, including newly defined literature-based specific age variations in carotid vessel properties. Simulated carotid flow/velocity waveforms, indexes, and age trends were statistically validated against in vivo data from the literature. A comprehensive study of the impact of aging on carotid flow waveform morphology was performed, and the mechanisms influencing different carotid indexes were elucidated. Notably, flow augmentation index (FAI) was found to be a strong indicator of local carotid stiffness.

Effect of transmural pressure on the estimation of arterial stiffness index from the photoplethysmographic waveform

The aim of this study was to find the effect of transmural pressure on the determination of the photoplethysmographic (PPG) waveform arterial stiffness index (PPGAI). The study was conducted on 51 subjects without diagnosis of cardiovascular disease, aged between 24 and 74 years. The relation between the transmural pressure, which is the difference between the arterial blood pressure and the PPG sensor contact pressure, and the PPGAI was determined. PPG, beat-to-beat blood pressure, and sensor contact pressure signals were recorded from the index, middle, and ring finger. The PPG sensor contact pressure of the index finger was increased from 20 to 120 mmHg. The aortic augmentation index (AIx@75) was estimated with a SphygmoCor device as a reference. High correlation coefficients r = 0.79 and r = 0.83 between PPGAI and AIx@75, and low PPGAI standard deviations were observed at the transmural pressures of 10 and 20 mmHg, respectively. Transmural pressure of 20 mmHg can be considered suitable for the PPG signal registration and PPGAI calculation for the assessment of arterial stiffness. In summary, the contact pressure of the sensor should be selected according to theblood pressure of the subject finger in order to achieve the transmural pressure suitable for the assessment of PPGAI and arterial stiffness.

Pulsatile microvascular cerebral blood flow waveforms change with intracranial compliance and age

Significance

Diffuse correlation spectroscopy (DCS) is an optical method to measure relative changes in cerebral blood flow (rCBF) in the microvasculature. Each heartbeat generates a pulsatile signal with distinct morphological features that we hypothesized to be related to intracranial compliance (ICC).

Aim

We aim to study how three features of the pulsatile rCBF waveforms: the augmentation index (AIx), the pulsatility index, and the area under the curve, change with respect to ICC. We describe ICC as a combination of vascular compliance and extravascular compliance.

Approach

Since patients with Chiari malformations (CM) (n = 30 ) have been shown to have altered extravascular compliance, we compare the morphology of rCBF waveforms in CM patients with age-matched healthy control (n = 30 ).

Results

AIx measured in the supine position was significantly less in patients with CM compared to healthy controls (p < 0.05 ). Since physiologic aging also leads to changes in vessel stiffness and intravascular compliance, we evaluate how the rCBF waveform changes with respect to age and find that the AIx feature was strongly correlated with age (R healthy subjects = - 0.63 , R preoperative   CM   patient = - 0.70 , and R postoperative   CM   patients = - 0.62 , p < 0.01 ).

Conclusions

These results suggest that the AIx measured in the cerebral microvasculature using DCS may be correlated to changes in ICC.

Arterial Stiffness and its Impact on Cardiovascular Health

PURPOSE OF REVIEW

Cardiovascular diseases are the leading cause of mortality globally. Identifying patients at risk is important to initiate preventive strategies. Over the last few decades, the role of the endothelium and its impact on arterial stiffness have been recognised as playing a pivotal role in cardiovascular disease. This review will focus on the effect of arterial stiffness in different patient cohorts with regard to cardiovascular morbidity and mortality, as well as its use in clinical practice.

RECENT FINDINGS

Arterial stiffness is associated with a range of cardiovascular risk factors and is an independent predictor of cardiovascular mortality. The gold standard for evaluating arterial stiffness is pulse wave velocity. Recently, cardio-ankle vascular index has been implemented as an easy and highly reproducible measure of arterial stiffness. Moreover, certain pharmacologic agents may modify arterial stiffness and alter progression of cardiovascular disease. The endothelium plays an important role in cardiovascular disease. Implementing assessment of arterial stiffness in clinical practice will improve stratification of patients at risk of cardiovascular disease and help modify disease progression.

Non-contact quantification of aortic stenosis and mitral regurgitation using carotid waveforms from skin displacements

Objective. Early diagnosis of heart problems is essential for improving patient prognosis.Approach. We created a non-contact imaging system that calculates the vessel-induced deformation of the skin to estimate the carotid artery pressure displacement waveforms. We present a clinical study of the system in patients (n= 27) with no underlying condition, aortic stenosis (AS), or mitral regurgitation (MR).Main results. Displacement waveforms were compared to aortic catheter pressures in the same patients. The morphologies of the pressure and displacement waveforms were found to be similar, and pulse wave analysis metrics, such as our modified reflection indices (RI) and waveform duration proportions, showed no significant differences. Compared with the control group, AS patients displayed a greater proportion of time to peak (p= 0.026 andp= 0.047 for catheter and displacement, respectively), whereas augmentation index (AIx)was greater for the displacement waveform only (p= 0.030). The modified RI for MR (p= 0.047 andp= 0.004 for catheter and displacement, respectively) was lower than in the controls. AS and MR were also significantly different for the proportion of time to peak (p= 0.018 for the catheter measurements), RI (p= 0.045 andp= 0.002 for the catheter and displacement, respectively), and AIx (p= 0.005 for the displacement waveform).Significance. These findings demonstrate the ability of our system to provide insights into cardiac conditions and support further development as a diagnostic/telehealth-based screening tool.

A comprehensive insight into the molecular effect of theobromine on cardiovascular-related risk factors: A systematic review of in vitro and in vivo studies

Theobromine may have beneficial effects on cardiovascular risk factors. This study aimed to find molecular effects of theobromine on lipid profile, glycemic status, inflammatory factors, and vascular function through a comprehensive assessment of all in vitro and in vivo studies. The search process was started at 18 July 2022. Databases including PubMed, Scopus, and Web of Science were searched to find all articles published up to 18 July 2022. Nineteen studies were included in this study. In vitro studies showed the improving effects of theobromine on inflammatory markers. Of four animal studies assessing the effect of theobromine on inflammatory markers, two reported favorable effects. Among five animal studies assessing the effects of theobromine on lipid profile, three reported improving effects on either triglyceride, total cholesterol, low- or high-density lipoprotein cholesterol. Of the three human studies, two revealed that theobromine had improving effects on lipid profile. A favorable effect of theobromine on augmentation index was also reported in two RCTs. The results for other outcomes were inconclusive. Theobromine may have favorable effects on inflammatory factors, lipid profile, and vascular function markers. However, studies with a longer duration and lower, dietary-relevant doses are required for future confirmation.

Vascular function and cognition in persons with multiple sclerosis: Preliminary examination

BACKGROUND

Cognitive dysfunction is one of the most common consequences of multiple sclerosis (MS). Recent studies have noted a high incidence of vascular comorbidity that might be associated with cognitive decline among persons with MS. However, there is a lack of evidence on vascular biomarkers (e.g., arterial stiffness indices) that are associated with cognition in MS. The current study characterized differences in vascular function between persons with MS and healthy controls, and examined the association between vascular and cognitive function in persons with MS compared with healthy controls.

RESULTS

The MS group had significantly worse cognitive performance and higher cfPWV than healthy controls. There were significant bivariate correlations between the Symbol Digit Modalities Test (SDMT) score with AIx75 (r_s = -0.45) and cfPWV (r_s = 0.30) in the MS sample, but not in healthy controls. Regression analyses further indicated a nonlinear association between cfPWV and the SDMT in the MS sample (p-values for β coefficients < 0.05; adjusted R² = 0.10). No significant associations were observed among other cognitive and vascular outcomes.

CONCLUSION

Our findings suggest significant associations between arterial stiffness and cognitive processing speed in MS. This preliminary examination provides initial, cross-sectional support for future population-based research on cognitive and vascular function in persons with MS. Such results may be clinically important for developing interventions that focus on regulating vascular dysfunction as an early treatment for preventing cognitive impairment in the MS population.

Clinical Factors Associated with Arterial Stiffness in Chronic Kidney Disease

BACKGROUND

Arterial stiffness influences the prognosis of patients with end-stage kidney disease; however, the factors that promote arterial stiffness in chronic kidney disease (CKD) patients remain unknown. We aimed to explore the clinical factors associated with arterial stiffness in CKD.

METHODS

Between September 2017 and September 2022, all CKD patients treated at the Department of Nephrology, General Hospital of the Chinese People's Liberation Army, excluding dialysis patients, were screened and their medical records within the last month were collected. Arterial stiffness was measured by the augmentation index (AIx). The correlative clinical factors with arterial stiffness were explored in different linear regression models.

RESULTS

559 patients were included in the study. AIx@75 increased as the deterioration of CKDG1-CKDG5, with values of 1 (-9, 11), 5.5 (-4, 13.25), 9 (0, 16), 12 (1.5, 23.5), and 22 (13, 28), respectively (Z = 63.03, p < 0.001). Multivariate linear regression analysis showed that AIx@75 was positively associated with female sex (β = 8.926, 95% confidence interval (CI) 6.291, 11.562, p < 0.001), age (β = 0. 485, 95% CI 0.39, 0.58, p < 0.001), mean arterial pressure (MAP) (β = 0.255, 95% CI 0.159, 0.35, p < 0.001), and was negatively associated with ACEI/ARB (β = -4.466, 95% CI -6.963, -1.969, p < 0.001) and glucocorticoid (β = -3.163, 95% CI -6.143, -0.183, p = 0.038). Smoking, eGFR, hemoglobin, and cause of disease were associated with AIx@75 in multivariate linear regression models when considering factors partly.

CONCLUSIONS

Female, age, smoking, MAP, eGFR, cause of disease, ACEI/ARB, and glucocorticoid were found to be associated with atherosclerosis in CKD patients.

Augmentation Index in Patients with Thoracic Aortic Aneurysm: A Matched Case-Control Study

Thoracic aortic aneurysms (TAA) may be associated with complications such as rupture and dissection, which can lead to a fatal outcome. Increased central arterial stiffness has been proposed to be present in patients with TAA compared to unmatched controls. We aimed to assess whether wall properties in patients with TAA are also altered when compared to a matched control group. Applanation tonometry was performed in 74 adults with TAA and 74 sex, age, weight, height, and left ventricular ejection fraction matched controls. Subsequently analysis of the pulse wave was done using the SphygmoCor System. For comparing the two groups, AIx was adjusted to a heart rate of 75/min (AIx@75). 148 1-to-1 matched participants were included in the final model. There was no significant difference in the Alx@75 between the TAA group and the matched control group [mean (SD) of 24.7 (11.2) % and 22.8 (11.2) %, p = 0.240]. Adjusted for known cardiovascular risk factors, there was no association between TAA and AIx@75. Patients with TAA showed comparable arterial wall properties to cardiovascular risk factor matched controls. Since higher arterial stiffness is associated with TAA progression, it remains to be investigated if increased central arterial stiffness is a relevant factor of TAA emergence.

The Effect of Age on Non-Invasive Hemodynamics in Chronic Heart Failure Patients on Left-Ventricular Assist Device Support: A Pilot Study

Background: Implantation of continuous flow left ventricular assist devices (LVAD’s) has been increasingly used in patients with advanced heart failure (HF). Little is known about the non-invasive hemodynamics and the relationship with adverse events in this specific group of patients. We aimed to identify any differences in non-invasive hemodynamics in patients with an LVAD in different age categories and to investigate if there is an association with major adverse events. Methods: In this observational cross-sectional study, HF patients with a continuous flow LVAD were included. Non-invasive hemodynamic parameters were measured with a validated, automated oscillometric blood pressure monitor. The occurrences of adverse events were registered by reviewing the medical records of the patients. An independent-samples T-test and Chi-square test were used to compare different groups of patients. Results: Forty-seven patients were included; of these, only 12 (25.6%) had a successful measurement. Heart rate, heart rate-adjusted augmentation index, and pulse wave velocity were higher in the ≥55 years of age LVAD group compared to the <55 years of age LVAD group (all p < 0.05). Stroke volume was significantly lower in the ≥55 years of age LVAD group compared to the <55 years of age LVAD group (p = 0.015). Patients with adverse events such as cardiovascular events, GI-bleeding, or admission to a hospital had lower central pulse pressure (cPP) than patients without any adverse event. Conclusion: Older LVAD patients have a significantly higher heart rate, heart rate-adjusted augmentation index, and pulse wave velocity and a significantly lower stroke volume compared to participants aged < 55 years. The pulsatile component of blood pressure was decreased in patients with adverse events.

Abdominal aortic aneurysm monitoring via arterial waveform analysis: towards a convenient point-of-care device

Abdominal aortic aneurysms (AAAs) are lethal but treatable yet substantially under-diagnosed and under-monitored. Hence, new AAA monitoring devices that are convenient in use and cost are needed. Our hypothesis is that analysis of arterial waveforms, which could be obtained with such a device, can provide information about AAA size. We aim to initially test this hypothesis via tonometric waveforms. We study noninvasive carotid and femoral blood pressure (BP) waveforms and reference image-based maximal aortic diameter measurements from 50 AAA patients as well as the two noninvasive BP waveforms from these patients after endovascular repair (EVAR) and from 50 comparable control patients. We develop linear regression models for predicting the maximal aortic diameter from waveform or non-waveform features. We evaluate the models in out-of-training data in terms of predicting the maximal aortic diameter value and changes induced by EVAR. The best model includes the carotid area ratio (diastolic area divided by systolic area) and normalized carotid-femoral pulse transit time ((age·diastolic BP)/(height/PTT)) as input features with positive model coefficients. This model is explainable based on the early, negative wave reflection in AAA and the Moens-Korteweg equation for relating PTT to vessel diameter. The predicted maximal aortic diameters yield receiver operating characteristic area under the curves of 0.83 ± 0.04 in classifying AAA versus control patients and 0.72 ± 0.04 in classifying AAA patients before versus after EVAR. These results are significantly better than a baseline model excluding waveform features as input. Our findings could potentially translate to convenient devices that serve as an adjunct to imaging.

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.

Central Aortic Pressure and Arterial Stiffness in Parkinson’s Disease: A Comparative Study

Background

Cardiovascular autonomic dysfunction, which leads to hemodynamic disorders, is commonly observed in patients with Parkinson's disease (PD). Central aortic pressure (CAP) is the systolic blood pressure (SBP) at the root of the aorta. In young people, CAP is lower than peripheral arterial blood pressure. In older people, the difference between CAP and peripheral arterial blood pressure decreases depending on the extent of arterial stiffness (AS). In patients with AS, CAP increases. CAP is thus regarded as an indicator of AS.

Objective

To compare CAP and other hemodynamic parameters for AS between patients with Parkinson's disease and control group. We also aimed to evaluate changes in these hemodynamic parameters after the levodopa (LD) intake.

Methods

We included 82 patients with PD and 76 healthy controls. Age, sex, disease duration, disease subtype, Hoehn–Yahr stage (H&Y), and nonmotor symptoms (NMS) were documented. TensioMed Software v.3.0.0.1 was used to measure CAP, peripheral arterial blood pressure, pulse pressure (PP), heart rate (HR), mean arterial pressure (MAP), augmentation index (AI), pulse wave velocity, and ejection time. All patients were being treated with LD, and measurements were performed 1 h before and 1 h after LD intake.

Results

Baseline peripheral arterial blood pressure and CAP values were significantly higher in the PD group than in the control group (p < 0.001 and p=0.02, respectively). Most cardiac hemodynamic parameters, including peripheral arterial blood pressure and CAP, decreased significantly (p < 0.02 and p < 0.001, respectively) after LD intake in the PD group. Disease subtype, duration, and severity did not affect any of the hemodynamic parameters. When NMS were evaluated, patients with psychosis and dementia showed higher baseline parameters.

Conclusion

Loss of postganglionic noradrenergic innervation is well-known with PD. Several cardiac hemodynamic parameters were affected, suggesting cardiac autonomic dysfunction in these patients. The data obtained were independent of disease severity, duration, and subtype. After LD intake, most of these parameters decreased, which might have a positive effect on the vascular burden.

High-intensity functional exercise does not cause persistent elevations in augmentation index in young men and women

Elevations in central augmentation index (AIx) are predictive of cardiovascular disease. Our objective was to examine AIx immediately and 24-hrs following an acute bout of high-intensity functional training (HIFT) in apparently healthy young adults. A second aim compared the exercise induced AIx recovery response between men and women. Thirty-two recreationally active younger adults (n=16 men) were tested. Baseline central hemodynamic measures were assessed, followed by a single bout of bodyweight HIFT. The HIFT included four rounds of burpees, jump squats, split squats, and walking lunges. Assessments were repeated 5-, 10-, 15- and 24-hrs post exercise. AIx was normalized to a heart rate of 75 bpm (AIx75). There was a significant main effect of time on AIx75 across all groups (p<0.001) with AIx75 increasing at all acute timepoints compared with baseline and returning to resting values 24-hrs post-exercise. When examining sex differences after covarying for height and body fat percentage, we found no time*sex interaction (p=0.62), or main effect for sex (p=0.41), but the significant main effect of time remained (p<0.001). The AIx75 response to HIFT follows a similar recovery pattern as previously studied modes of exercise with no residual effects 24 hrs later and no differences between men and women indicating no persistent cardiovascular strain in younger adults participating in this mode of exercise.

The relationship of endothelial function and arterial stiffness with subclinical target organ damage in essential hypertension

This study aimed to explore whether brachial‐ankle pulse wave velocity (baPWV) and brachial artery flow‐mediated dilation (FMD) or the interaction of both parameters are associated with subclinical target organ damage (STOD) indices in patients with essential hypertension. A total of 4618 patients registered from January 2015 to October 2020 were included. baPWV and FMD were measured to evaluate arterial stiffness and endothelial dysfunction. Whereas left ventricular hypertrophy (LVH), urine albumin‐creatinine ratio (UACR), and carotid intima‐media thickness (CIMT) were obtained as STOD indicators. On multivariable logistic regression analysis with potential confounders, higher quartiles of baPWV and FMD were significantly associated with an increased risk of STOD. In patients <65 years of age, the odds ratio (OR) of LVH, UACR, and CIMT ≥.9 mm for the fourth versus the first quartile of baPWV were 1.765 (1.390–2.240), 2.832 (2.014–3.813), and 3.075 (2.315–4.084), respectively. In interaction analysis, an increase in baPWV shows a progressively higher risk of STOD across the quartiles of FMD. Also, the estimated absolute risks of LVH, UACR, and CIMT ≥.9 mm for the first to fourth quartile of baPWV increased from 1.88 to 2.75, 2.35 to 4.44, and 3.10 to 6.10, respectively, in patients grouped by FMD quartiles. The addition of baPWV to FMD slightly improved risk prediction for STOD. BaPWV and FMD were independently associated with an increased risk of STOD in patients with essential hypertension especially among patients <65 years of age. Patients with elevated baPWV and decreased FMD parameters are at increased risk of STOD.

L-Citrulline supplementation attenuates aortic pulse pressure and wave reflection responses to cold stress in older adults

BACKGROUND AND AIMS

Augmented aortic systolic blood pressure (SBP) and wave reflection via sympathetic-mediated vasoconstriction elevates the risk for adverse cardiovascular events in older adults. L-citrulline (L-CIT) supplementation has shown to reduce aortic SBP and pulse pressure (PP) responses to cold pressor test (CPT) induced sympathoactivation in young men. The aim of this study was to elucidate the efficacy of L-CIT supplementation to attenuate aortic hemodynamic responses to CPT in older adults.

METHODS AND RESULTS

Sixteen older adults were randomly assigned to placebo or L-CIT (6 g/day) for 14-days in a crossover, double-blind, placebo-controlled design. Brachial SBP and aortic SBP, PP, augmented pressure (AP), augmentation index standardized at 75 bpm (AIx@75), and pressure of the forward (Pf) and reflected (Pb) waves were evaluated at rest and during CPT pre- and post-intervention. Although no hemodynamic changes at rest, brachial SBP (Δ-12 ± 18 vs. Δ4 ± 14 mmHg; P = 0.008) and aortic SBP (Δ-10 ± 14 vs. Δ4 ± 12 mmHg; P = 0.005), PP (Δ-10 ± 12 vs. Δ4 ± 11 mmHg; P = 0.002), AP (Δ-4 ± 4 vs. Δ2 ± 7 mmHg; P = 0.004), AIx@75 (Δ-3.2 ± 7.2 vs. Δ2.2 ± 6.9%; P = 0.038), Pf (Δ-6 ± 10 vs. Δ3 ± 9 mmHg; P = 0.019), and Pb (Δ-4 ± 6 vs. Δ2 ± 6 mmHg; P = 0.008) responses to the CPT were significantly attenuated following L-CIT supplementation vs. placebo.

CONCLUSIONS

L-CIT supplementation attenuated aortic pulsatile pressure and pressure wave reflection responses to CPT in older adults, providing possible cardioprotection during cold-induced sympathoactivation in older adults.

The central arterial stiffness parameters in decompensated versus compensated states of heart failure: a paired comparative cohort study

Background

Arterial stiffness is strongly linked to the pathogenesis of heart failure and the development of acute decompensation in patients with stable chronic heart failure. This study aimed to compare arterial stiffness indices in patients with heart failure with reduced ejection fraction (HFrEF) during the acute decompensated state, and three months later after hospital discharge during the compensated state.

Results

One hundred patients with acute decompensated HFrEF (NYHA class III and IV) and left ventricular ejection fraction ≤ 35% were included in the study. During the initial and follow-up visits, all patients underwent full medical history taking, clinical examination, transthoracic echocardiography, and non-invasive pulse wave analysis by the Mobil-O-Graph 24-h device for measurement of arterial stiffness. The mean age was 51.6 ± 6.1 years and 80% of the participants were males. There was a significant reduction of the central arterial stiffness indices in patients with HFrEF during the compensated state compared to the decompensated state. During the decompensated state, patients presented with NYHA FC IV (n = 64) showed higher AI (24.5 ± 10.0 vs. 16.8 ± 8.6, p < 0.001) and pulse wave velocity (9.2 ± 1.3 vs. 8.5 ± 1.2, p = 0.021) than patients with NYHA FC III, and despite the relatively smaller number of females, they showed higher stiffness indices than males.

Conclusions

Central arterial stiffness indices in patients with HFrEF were significantly lower in the compensated state than in the decompensated state. Patients with NYHA FC IV and female patients showed higher stiffness indices in their decompensated state of heart failure.

Arterial stiffness measurements in pregnancy as a predictive tool for hypertensive disorders of pregnancy and preeclampsia: Protocol for a systematic review and meta-analysis

Hypertensive disorders of pregnancy (HDPs) are a leading cause of maternal morbidity and mortality worldwide. Unfortunately, accurate early clinical screening methods for the development of these disorders are lacking. Arterial stiffness (AS) is an important hemodynamic indicator of vascular health that has shown promising results for the prediction of HDP onset. Past systematic reviews in the field have reported an increase in AS indices in women who develop HDPs and have highlighted the potential of AS measurements as a predictive tool early in pregnancy. The most recent systematic review, including papers up to 2015, assessed the differences in AS parameters between women with and without pregnancy complications. Since then, there has been a substantial influx of published research on the topic and a growing interest in the incorporation of AS measurements into clinical practice. Thus, we propose a systematic review and meta-analysis that is more inclusive to all HDP subsets and various hemodynamic indices of vascular health to provide a comprehensive overview of the current state of evidence. Specifically, we aim to evaluate these measures in women who develop HDPs compared to normotensive pregnancies to determine which measures are most associated with and/or can predict the development of HDPs. Major databases (Medline, Embase, The Cochrane Library, Web of Science, PubMed, and CINAHL), grey literature (Google Scholar) and clinical trials (clinicaltrials.gov) will be searched to identify studies that report AS and hemodynamic measurements in pregnant women with and without HDPs. No restrictions will be made on study type or year. Articles will be independently evaluated by three authors to determine eligibility based on inclusion and exclusion criteria. Methodological quality of included studies will be assessed. Pooled analyses will be conducted using a random-effects model. Publication bias and between-study heterogeneity will also be assessed. Sources of heterogeneity will be explored by sensitivity, subgroup, and/or meta-regression analyses. Results from this study will be shared through scientific conferences and publications in scientific journals. The analysis of potential AS and hemodynamic markers for HDP onset will help inform the development of screening guidelines and clinically relevant cut-off values of AS and hemodynamic markers for HDP risk, guiding future research. There are no applicable ethical considerations to the writing of this protocol.

Total vascular resistance, augmentation index, and augmentation pressure increase in patients with peripheral artery disease

Peripheral arterial disease (PAD) is one of major vascular diseases which frequently coexists with coronary arterial disease and cerebrovascular disease. The patients with PAD have a poor prognosis when it progresses. A new blood pressure testing device enables to simultaneously measure brachial blood pressure (BP), central BP, and several vascular parameters, with easy and non-invasive, in a short time. Here, we aimed to evaluate these arterial stiffness parameters in patients with PAD.In this study, 243 consecutive patients who were suspected of having PAD and referred to our hospital from September 2016 to June 2019, were registered. Several parameters, such as brachial BP, central BP, aortic pulse wave velocity (aPWV), total vascular resistance (TVR), augmentation index (AI) and augmentation pressure (AP), were determined by Mobil-O-Graph. Ankle-brachial pressure index (ABI) was used to define PAD (ABI ≤ 0.9 as PAD). The relationship between PAD and central BP, aPWV, TVR, AI, or AP were investigated.One hundred sixty-two patients (67%) were categorized as the PAD group and 81 patients (33%) as the non-PAD group. In the PAD group, the systolic brachial BP and central systolic BP were significantly higher than those in the non-PAD group (138 ± 24 mmHg vs 131 ± 19 mmHg, P < .05, 125 ± 22 mmHg vs 119 ± 18 mmHg, P < .05, respectively). TVR, AI, and AP were significantly higher in the PAD group (1785 ± 379 dyn s/cm5 vs 1661 ± 317 dyn s/cm5, P < .05, 26.2 ± 13.0% vs 22.2 ± 13.3%, P < .05, 13.5 ± 9.4 mmHg vs 10.7 ± 7.2 mmHg, P < .05, respectively). No significant differences in diastolic BP, central diastolic BP, and aPWV were found between the groups. Multivariate logistic regression analysis revealed that PAD was significantly associated with TVR, AI, and AP (P < .05, respectively).TVR/AP/AI were significantly higher in the PAD group than in the non-PAD group.

Relationship between Augmentation Index and Wall Thickening Fraction during Hypotension in an Animal Model of Myocardial Ischemia-Reperfusion and Heart Failure

AIMS

Non-invasive indices to evaluate left ventricular changes during ischemic heart failure are needed to quantify the myocardial impairment and the effectiveness of therapeutic manoeuvres. The aims of this work were to calculate the Wall Thickening Fraction (WTF) and the Augmentation Index (AIx) and to assess the relationship between WTF and AIx using data obtained from an animal model with heart failure followed by a myocardial ischemia stage and a reperfusion stage.

METHODS

Nine Corriedale sheep that had been monitored for 10 minutes during a basal stage underwent 5-minute myocardial ischemia, followed by 60-minute reperfusion. Seven of them were subjected to an induced heart failure through an overdose of halothane, two of which were treated with intra-aortic counterpulsation during the reperfusion stage. The remaining two animals were monitored during their ischemia-reperfusion stage.

RESULTS

Data obtained in the 5 animals suffering from heart failure followed by myocardial ischemia showed that: a) heart failure induction determined decrease in cardiac output, cardiac index and systolic and diastolic aortic pressure (AoP) with respect to their basal values (p<0.05), b) myocardial ischemia decreased the WTF compared with basal and induced heart failure values (p<0.05), c) during the reperfusion stage accompanied by induced heart failure, WTF increased with respect to values observed during the ischemia induction stage (p<0.05); nevertheless, basal values were not recovered after reperfusion (p<0.05). During this 60-minute stage, systolic and diastolic AoP values were lower (p<0.05) than those at the basal stage.

CONCLUSION

AIx and WTF values calculated from synchronically recorded values of aortic pressure and left ventricular wall thickness during the reperfusion stage in all animals (n = 9) showed a negative correlation (p<0.05). Analysed data provided evidence of a negative relationship between a left ventricular index of myocardial function and an arterial index obtained from AoP waves.

Subclinical vasculopathy and skeletal muscle metrics in the singapore longitudinal ageing study

Frailty is associated with future cardiovascular events in older adults. This cross-sectional study examined the relationship between subclinical vasculopathy with measures of skeletal muscle mass and function. Asymptomatic community-dwelling Asians ≥55 years underwent assessments for subclinical vasculopathy (carotid intima-media thickness (cIMT), aortic and carotid stiffness, and endothelial function), muscle mass (calf circumference adjusted for body mass index) and function (knee extension strength, 6-meter fast gait speed). Multivariable regression analyses for associates of muscle mass/function controlled for demographics and cardiometabolic risk factors. Among 336 participants (median age 62 years, 55.1% male, 3.6% sarcopenia), cIMT, aortic and carotid stiffness inversely correlated with muscle mass, strength and gait speed; cIMT remained independently associated with gait speed (β=-0.26) in multivariable analyses. Age and sex significantly modified the relationship between subclinical vasculopathy and muscle mass/function. Associations, only found in those aged ≥70, included cIMT with gait speed (β=-0.48) and knee strength (β=-9.33), and aortic augmentation index and aortic stiffness composite z-score with gait speed (β=-0.11 and β=-0.19 respectively). Among males, cIMT correlated with gait speed (β=-0.31). The association of subclinical vasculopathy with skeletal muscle mass and function in asymptomatic adults ≥55 years is best reflected by cIMT. The roles of mediating pathways deserve further evaluation.

Augmentation Index Predicts the Sweat Volume in Young Runners

Sweating during exercise is regulated by objective parameters, body weight, and endothelial function, among other factors. However, the relationship between vascular arterial stiffness and sweat volume in young adults remains unclear. This study aimed to identify hemodynamic parameters before exercise that can predict sweat volume during exercise, and post-exercise parameters that can be predicted by the sweat volume. Eighty-nine young healthy subjects (aged 21.9 ± 1.7 years, 51 males) were recruited to each perform a 3-km run on a treadmill. Demographic and anthropometric data were collected and hemodynamic data were obtained, including heart rate, blood pressure and pulse wave analysis using non-invasive tonometry. Sweat volume was defined as pre-exercise body weight minus post-exercise body weight. Post-exercise hemodynamic parameters were also collected. Sweat volume was significantly associated with gender, body surface area (BSA) (b = 0.288, p = 0.010), peripheral systolic blood pressure (SBP), peripheral and central pulse pressure (PP), and was inversely associated with augmentation index at an HR of 75 beats/min (AIx@HR75) (b = -0.005, p = 0.019) and ejection duration. While BSA appeared to predict central PP (B = 19.271, p ≤ 0.001), central PP plus AIx@HR75 further predicted sweat volume (B = 0.008, p = 0.025; B = -0.009, p = 0.003 respectively). Sweat volume was associated with peripheral SBP change (B = -17.560, p = 0.031). Sweat volume during a 3-km run appears to be influenced by hemodynamic parameters, including vascular arterial stiffness and central pulse pressure. Results of the present study suggest that vascular arterial stiffness likely regulates sweat volume during exercise.

Wave reflection: More than a round trip

Reflected pressure waves are key to the understanding of vascular ageing, a prominent factor in major cardiovascular events. Several different metrics have been proposed to index the effect of wave reflection on the pressure waveform and thereby serve as an indicator of vascular ageing. The extent to which these indices are influenced by factors other than vascular health remains a matter of concern. In this paper, we use transmission-line theory to derive a mathematical model for the reflection time (T_refl), and the augmentation index (AI), assuming a general extended model of the arterial system. Then, we test the proposed model against values reported in the literature. Finally, we discuss insights from the model to common observations in the literature such as age-related "shift" in the reflection site, the variation of AI with heart rate, and the flattening of T_refl in older participants.

Carotid stiffness, intima-media thickness and aortic augmentation index among adults with SARS-CoV-2

New Findings

What is the central question of this study?

We sought to investigate whether carotid stiffness, carotid intima–media thickness and the aortic augmentation index are altered in young adults 3–4 weeks after contraction of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) compared with young healthy adults.

What is the main finding and its importance?

We found that carotid stiffness, Young's modulus and the aortic augmentation index were greater in young adults who tested positive for SARS‐CoV‐2 compared with healthy young adults. These findings provide additional evidence for detrimental effects of SARS‐CoV‐2 on young adult vasculature, which might have implications for cardiovascular health.

Abstract

Contracting severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has been observed to cause decrements in vascular function of young adults. However, less is known about the impact of SARS‐CoV‐2 on arterial stiffness and structure, which might have additional implications for cardiovascular health. The purpose of this study was to assess the carotid artery stiffness and structure using ultrasound and the aortic augmentation index (AIx) using applanation tonometry in young adults after they tested positive for SARS‐CoV‐2. We hypothesized that carotid artery stiffness, carotid intima–media thickness (cIMT) and aortic AIx would be elevated in young adults with SARS‐CoV‐2 compared with healthy young adults. We evaluated 15 young adults (six male and nine female; 20 ± 1 years of age; body mass index, 24 ± 3 kg m⁻²) 3–4 weeks after a positive SARS‐CoV‐2 test result compared with young healthy adults (five male and 10 female; 23 ± 1 years of age; body mass index, 22 ± 2 kg m⁻²) who were evaluated before the coronavirus 2019 pandemic. Carotid stiffness, Young's modulus and cIMT were assessed using ultrasound, whereas aortic AIx and aortic AIx standardized to 75 beats min⁻¹ (AIx@HR75) were assessed from carotid pulse wave analysis using SphygmoCor. Group differences were observed for carotid stiffness (control, 5 ± 1 m s⁻¹; SARS‐CoV‐2, 6 ± 1 m s⁻¹), Young's modulus (control, 396 ± 120 kPa; SARS‐CoV‐2, 576 ± 224 kPa), aortic AIx (control, 3 ± 13%; SARS‐CoV‐2, 13 ± 9%) and aortic AIx@HR75 (control, −3 ± 16%; SARS‐CoV‐2, 10 ± 7%; P < 0.05). However, cIMT was similar between groups (control, 0.42 ± 0.06 mm; SARS‐CoV‐2, 0.44 ± 0.08 mm; P > 0.05). This cross‐sectional analysis revealed higher carotid artery stiffness and aortic stiffness among young adults with SARS‐CoV‐2. These results provide further evidence of cardiovascular impairments among young adults recovering from SARS‐CoV‐2 infection, which should be considered for cardiovascular complications associated with SARS‐CoV‐2.

Impaired pulse pressure amplification, augmentation index, and arterial stiffness are associated with reduced limb lean mass in overweight and obese postmenopausal women

BACKGROUND

The age-related muscle mass loss has been associated with increased arterial stiffness (brachial-ankle pulse wave velocity, baPWV) and wave reflection (augmentation index, AIx). In healthy individuals, pulse pressure (PP) is lower in the aorta compared to the brachial artery (PP amplification, PPA). Postmenopausal women experience elevated aortic stiffness leading to increased AIx and aortic PP causing reduced PPA, an independent predictor of cardiovascular mortality. It is unknown whether appendicular skeletal muscle index (ASMI), arm (ArmLM) or leg lean mass (LegLM) are negatively associated with PPA. The purpose of this study was to investigate the associations between vascular function (PPA, AIx, and baPWV) and lean mass (ASMI, ArmLM, and LegLM) in postmenopausal women.

METHODS

The study was performed in 93 postmenopausal women (48-71 years; BMI: 30 ± 7 kg/m²). PPA (brachial/aortic PP), aortic AIx, and baPWV were measured. ArmLM and LegLM were measured by dual-energy X-ray absorptiometry. ASMI was calculated as (ArmLM+LegLM)/Ht². Associations between vascular and lean mass measures were analyzed by multiple linear regression.

RESULTS

PPA was associated with ASMI (β = 0.29, p = .016) and LegLM (β = 0.25, p = .028) after adjustment for age, height, systolic pressure, strength, and heart rate. AIx was associated with ASMI (β = -0.27, p = .011), ArmLM (β = -0.25, p = .023), and LegLM (β = -0.22, p = .026), while baPWV was associated with reduced ASMI (β = -0.23, p = .043) and ArmLM (β = -0.23, p = .045), but not with LegLM (β = -0.19, p = .074) after full adjustment.

CONCLUSIONS

Our findings indicate that impaired pulsatile hemodynamics (PPA and AIx) are negatively associated with ASMI and LegLM, while arterial stiffness is negatively associated with ASMI and ArmLM. Thus, vascular dysfunction may be implicated in muscle mass loss in overweight and obese postmenopausal women.

Acute effects of transcatheter aortic valve replacement on the ventricular-aortic interaction

Transcatheter aortic valve replacement (TAVR) is linked with an immediate increase in aortic systolic blood pressure and maximal flow, as well as steeper aortic pressure and flow wave upstrokes. After TAVR, the forward wave pumped by the heart is enhanced. Although the arterial properties remain unchanged, the central augmentation index (AIx) is markedly decreased after TAVR. This challenges the interpretation of AIx as a solely vascular measure in patients with aortic valve stenosis.

Measurement, Analysis and Interpretation of Pressure/Flow Waves in Blood Vessels

The optimal performance of the cardiovascular system, as well as the break-down of this performance with disease, both involve complex biomechanical interactions between the heart, conduit vascular networks and microvascular beds. ‘Wave analysis’ refers to a group of techniques that provide valuable insight into these interactions by scrutinizing the shape of blood pressure and flow/velocity waveforms. The aim of this review paper is to provide a comprehensive introduction to wave analysis, with a focus on key concepts and practical application rather than mathematical derivations. We begin with an overview of invasive and non-invasive measurement techniques that can be used to obtain the signals required for wave analysis. We then review the most widely used wave analysis techniques—pulse wave analysis, wave separation and wave intensity analysis—and associated methods for estimating local wave speed or characteristic impedance that are required for decomposing waveforms into forward and backward wave components. This is followed by a discussion of the biomechanical phenomena that generate waves and the processes that modulate wave amplitude, both of which are critical for interpreting measured wave patterns. Finally, we provide a brief update on several emerging techniques/concepts in the wave analysis field, namely wave potential and the reservoir-excess pressure approach.

Conduit arterial wave reflection promotes pressure transmission but impedes hydraulic energy transmission to the microvasculature

With aging, a reduction in the stiffness gradient between elastic and muscular arteries is thought to reduce wave reflection in conduit arteries, leading to increased pulsatile pressure transmission into the microvasculature. This assumes that wave reflection limits pressure transmission in arteries. However, using a computational model, we showed that wave reflection promotes pulsatile pressure transmission, although it does limit hydraulic energy transmission. Increased microvascular pulse pressure with aging is instead related to decreasing arterial compliance.

Association of particles of lipoprotein subclasses with arterial stiffness in a high-risk working population: the Baptist Employee Healthy Heart Study (BEHHS)

Background

Arterial stiffness is an independent predictor of cardiovascular disease (CVD) morbidity and mortality. A risk factor-independent association of arterial stiffness with traditional lipids has been described extensively, but it is still unclear whether an independent relationship exists between arterial stiffness and particles of lipoprotein subclasses.

Methods

The Baptist Employee Healthy Heart Study (BEHHS) is a lifestyle intervention study examining the effects of web-based programs on reducing CVD risk in high-risk persons. Participants had their brachial arterial augmentation index (AI, a measure arterial stiffness) assessed using the EndoPAT 2000 device. Cardio IQ™ ion mobility lipoprotein fractionation was utilized for measurement of particles of lipoprotein subclasses.

Results

The population consisted of 182 participants, (74% women, 49% Hispanic) with a mean age of 52 ± 9 years. There was a significant trend association between quartiles of AI and total cholesterol, HDL-c, large LDL-p, small IDL-p, large IDL-p, and all subclasses of HDL particles (total HDL-p, small HDL-p, and large HDL-p). In logistic regression analysis, only HDL-c, total LDL-p, large LDL-p, small IDL-p, large IDL-p, total HDL-p, small HDL-p, and large HDL-p demonstrated significant independent association with AI.

Conclusion

Several lipoprotein subclasses demonstrate independent significant associations with arterial stiffness. A safe and relatively inexpensive blood test may be useful in identifying subclinical atherosclerosis process in a relatively young high CVD risk population.

Trial registration

ClinicalTrials.gov, NCT01912209. Registered July 31, 2013

Is there an association between the parameters of arterial stiffness and tinnitus?

Background: Increasing arterial stiffness is associated with atherosclerosis and there is an association between atherosclerosis and tinnitus may occur.Objectives: The aim of this study was to investigate the relationship between arterial stiffness and tinnitus using the central pulse-wave analysis method.Methods: This prospective, single center study included 98 participants, comprising 49 patients diagnosed with subjective idiopathic tinnitus (Group 1) and a control group of 49 healthy subjects (Group 2). The Mobil-O-Graph 24 h Pulse wave analysis (PWA) Monitor (I.E.M. GmbH, Stolberg, Germany) was used to determine the arterial stiffness and cardiovascular hemodynamic parameters. Central pulse pressure (CPP), Augmentation index and pulse wave velocity (PWV) were obtained with the device.Results: No statistically significant difference was determined between Groups in respect of age, smoking and hypertension (p > .05). Statistically significantly higher Central Pulse Pressure (CPP) values and pulse wave velocity were higher in Group 1 compared to the control group (p < .005). No statistical variation was detected in terms of the augmentation index (18.5 ± 11.3 vs 16.7 ± 10.3, p = .543).Conclusion: Our results marked that arterial stiffness is associated with tinnitus. The relationship was examined via oscillometric method, which is simple to perform and has been recommended in guidelines for the determination of cardiovascular event risk.

Cardiac magnetic resonance assessment of aortic distensibility in prediabetic patients

Background

Hyperglycemia, insulin resistance, and hyperinsulinemia represent important pathophysiological components of the prediabetic stage that result in arteriosclerosis and increased arterial stiffness. We sought to compare the aortic distensibility (AD) assessed by cardiac magnetic resonance (CMR) in prediabetic patients presenting with chronic coronary artery disease (CCAD) versus patients with normal HbA1C. Ninety-eight patients with CCAD were recruited. All patients were screened for HbA1C levels and then underwent a CMR study to assess AD of the aortic root and the ascending and descending thoracic aorta. Patients were classified into two groups: 52 prediabetic (HbA1C 5.7–6.4%) (study group) and 46 with normal glycemic status (HbA1C < 5.7%) (control group).

Results

AD values at the aortic root (AR) (13.93 ± 5.17 vs 34.3 ± 9.65 Kpa^-1 × 10^-3), ascending aorta (AA) (13.17 ± 4.81 vs 28.1 ± 8.33 Kpa^-1 × 10^-3), and descending thoracic aorta (DA) (18.12 ± 4.34 vs 33.68 ± 7.57 Kpa^-1 × 10^-3) were significantly lower in the study group than in the control group (P value for all was < 0.001). Twenty-eight patients fulfilled the criteria for metabolic syndrome, and in those patients, AD was significantly lower than in those without metabolic syndrome.

Aortic distensibility at the AR, AA, and DA had strong significant negative correlations with the level of glycosylated hemoglobin (AA, AR, DA; r − 0.66, − 0.68, − 0.58, respectively) (P < 0.001).

Conclusion

AD values at different points (AR, AA, and DA) were significantly lower in prediabetic and metabolic syndrome patients than in controls. These values also showed a significant negative correlation with the levels of HBA1C.

Exaggerated Aortic Pulse Pressure and Wave Amplitude During Muscle Metaboreflex Activation in Type 2 Diabetes Patients

BACKGROUND

Peripheral mean arterial pressure (MAP) responses to muscle metaboreflex activation using postexercise muscle ischemia (PEMI) in type 2 diabetes patients (T2D) are contradictory. Given that aortic pulse pressure (PP) and wave reflections are better indicators of cardiac load than peripheral MAP, we evaluated aortic blood pressure (BP) and wave amplitude during PEMI.

METHODS

Aortic BP and pressure wave amplitudes were measured at rest and during PEMI following isometric handgrip at 30% maximum voluntary contraction (MVC) in 16 T2D and 15 controls. Resting aortic stiffness (carotid-femoral pulse wave velocity, cfPWV) and fasting blood glucose (FBG) were measured.

RESULTS

Increases in aortic MAP (Δ26 ± 2 mmHg vs. Δ17 ± 2 mmHg), PP (Δ15 ± 2 mmHg vs. Δ10 ± 1 mmHg), augmentation index (AIx) (Δ8.2 ± 1.0% vs. Δ4.5 ± 1.3%), augmented pressure (AP) (Δ11 ± 1 mmHg vs. Δ5 ± 1 mmHg), forward (Pf) (Δ9 ± 1 mmHg vs. Δ5 ± 1 mmHg), and backward pressure waves (Pb) (Δ10 ± 1 mmHg vs. Δ5 ± 1 mmHg) responses to PEMI were greater in T2D than controls (P < 0.05). Aortic PP, but not MAP, response to PEMI was correlated to Pf (r = 0.63, P < 0.001) and Pb (r = 0.82, P < 0.001) responses and cfPWV (r = 0.37, P < 0.05).

CONCLUSIONS

Aortic BP and pressure wave responses to muscle metaboreflex activation are exaggerated in T2D. Aortic PP during PEMI was related to increased wave reflection, forward wave amplitude, and aortic stiffness in T2D patients.

Modulation of endothelial cell responses and vascular function by dietary fatty acids

Healthy and functional endothelial cells play important roles in maintaining vascular homeostasis, whereas endothelial dysfunction initiates and exacerbates vascular disease progression. Interventional studies with dietary fatty acids have shown that these molecules have varying effects on vascular function. It is hypothesized that the actions of dietary fatty acids on vascular function may be mediated in part through endothelial cells. This review summarizes the results of studies that have examined the acute and chronic effects of dietary fatty acids on endothelial function and vascular properties in humans, as well as the potential mechanisms by which n-3 polyunsaturated fatty acids regulate endothelial function. Altogether, this article provides an extensive review of how fatty acids contribute to vascular function through their ability to modulate endothelial cells and discusses relationships between dietary fatty acids and endothelial cells in the context of vascular dysfunction.

Augmentation index in the assessment of wave reflections and systolic loading

BACKGROUND

Augmentation index (AI_x) is used to quantify the augmented systolic aortic pressure that impedes ventricular ejection. Its use as an index of wave reflections is questionable. We hypothesize that AI_x is quantitatively different from the reflection coefficient under varied physiological conditions.

METHODS

42 datasets of aortic pressure and flow waveforms were obtained during induced hypertension (methoxamine infusion) and vasodilation (nitroprusside infusion) in our mongrel dog experiments (n = 5) and from Mendeley data during various interventions (vasoconstrictors, vasodilators, pacing, stimulation, hemorrhage and hemodilution). Wave reflections and principal components of reflection coefficients were computed for comparison to AI_x and heart rate normalized AI_x. RESULTS: Principal reflection coefficient, Γ₁, increased in hypertension and decreased in vasodilation, hemorrhage and hemodilution. AI_x followed the trend in many cases but was consistently lower than Γ₁ in almost all the subjects. The Bland-Altman analysis also showed that both AI_x and normalized AI_x underestimated Γ₁. The relationship between augmentation index and reflection coefficient was explained by a linear regression model (r² = 0.23, p < 0.01) in which AI_x followed directional changes in Γ₁ and the normalization of AI_x resulted in a linear model that explained less variation in the relationship between AI_x and Γ₁.

CONCLUSION

AI_x is a reasonable clinical trend indicator, albeit not an accurate surrogate measure of the amount of wave reflections.

Aortic Augmentation Index is Dependent on Bodyside in Healthy Young Subjects

INTRODUCTION

Aortic augmentation index (AIx) is a commonly used measure to evaluate the arterial stiffness of large elastic arteries. It has been used as an indicator for cardiovascular risk in clinical practice.

AIM

To evaluate the difference in the aortic AIx assessed from the left and the right hand in a group of healthy young adults using SphygmoCor and Arteriograph devices.

METHODS

32 subjects were enrolled in this study (27 ± 7 years), 16 male and 16 female volunteers participated. Equally, half of the gender groups were left-handed and another half right-handed.

RESULTS

It was found that the aortic AIx values assessed from the pressure waveforms of the right and the left hand are different and significantly higher in the left hand. Using a SphygmoCor device, the mean difference between the aortic AIx values from the right and the left hand among the whole study group was found - 4.78 ± 4.31% and using an Arteriograph the aortic AIx values were - 3.92 ± 3.90%. Aortic AIx values assessed from the right and the left hand were linearly related to each other for both devices. Moreover, it was found that the values of the aortic.

CONCLUSIONS

AIx are independent of the subject's handedness. It has to be pointed out that subjects who cannot be subjected to assessment of the aortic AIx from one side of the body could have different AIx values estimated from the recorded pressure waveform from the other bodyside.

Burden of Cardiovascular Risk Factors Over Time and Arterial Stiffness in Youth With Type 1 Diabetes Mellitus: The SEARCH for Diabetes in Youth Study

Background The incidence of type 1 diabetes mellitus (T1DM) in children is increasing, resulting in higher burden of cardiovascular diseases due to diabetes mellitus-related vascular dysfunction. Methods and Results We examined cardiovascular risk factors ( CVRF s) and arterial parameters in 1809 youth with T1DM. Demographics, anthropometrics, blood pressure, and laboratory data were collected at T1DM onset and 5 years later. Pulse wave velocity and augmentation index were collected with tonometry. ANOVA or chi-square tests were used to test for differences in measures of arterial parameters by CVRF . Area under the curve of CVRF s was entered in general linear models to explore determinants of accelerate vascular aging. Participants at the time of arterial measurement were 17.6±4.5 years old, 50% female, 76% non-Hispanic white, and duration of T1DM was 7.8±1.9 years. Glycemic control was poor (glycated hemoglobin, 9.1±1.8%). All arterial parameters were higher in participants with glycated hemoglobin ≥9% and pulse wave velocity was higher with lower insulin sensitivity or longer duration of diabetes mellitus. Differences in arterial parameters were found by sex, age, and presence of obesity, hypertension, or dyslipidemia. In multivariable models, higher glycated hemoglobin, lower insulin sensitivity, body mass index, blood pressure, and lipid areas under the curve were associated with accelerated vascular aging. Conclusions In young people with T1DM, persistent poor glycemic control and higher levels of traditional CVRF s are independently associated with arterial aging. Improving glycemic control and interventions to lower CVRF s may prevent future cardiovascular events in young individuals with T1DM.

Presence of tophi is a predictive factor of arterial stiffness in patients with gout

The objective of this study is to determine whether the presence of tophi could predict an increase in arterial stiffness. Between June 2017 and June 2018, the augmentation index (AI) was measured using SphygmoCor^® for patients with gout who visited the Jeju National University Hospital in South Korea. Patients were divided into the following groups: group with tophi and group without tophi. Medical records, laboratory data, and AI were retrospectively analyzed. One hundred and twenty patients with gout or participated in the study, with most (96.7%) of the patients being male. The mean duration of the disease was 7.0 years. At the time of the examination, 99 patients (82.5%) were treated with a uric acid-lowering agent. Of the total patients, 24 (19.7%) had tophi. Patients with tophi were significantly older (60.2 ± 11.6 years vs. 53.8 ± 13.0 years, p = 0.031), had longer disease duration (13.0 ± 6.5 years vs 5.5 ± 5.4 years, p < 0.001), and higher AI@75 (28.7 ± 7.8 vs 20.9 ± 10.0, p = 0.001) than those without tophi. In the multiple linear regression analysis, tophi was shown to be a significant predictor of high AI (p = 0.040). The presence of tophi is a predictor of increased arterial stiffness in patients with gout. Therefore, more strict control of cardiovascular disease risk factors is needed in the treatment of patients with tophi.