Pulse wave analysis using the Mobil-O-Graph, Arteriograph and Complior device: a comparative study

No association between vascular aging and sarcopenia in healthy participants

BACKGROUND & AIMS

Several reports inform an association between vascular aging and sarcopenia. However, both conditions appear along with aging. Therefore, their association may be circumstantial and not casually linked. Our aim was to determine if individuals with higher-than-expected vascular aging have a higher frequency of sarcopenia.

METHODS

In 802 participants we calculated the association between pulse wave pressure and carotid intima media thickness and age and blood pressure, to derive predictive regression equations. In 161 of these participants we measured body composition by double beam X ray absorptiometry (DEXA), hand grip strength, rectus femoris thickness by ultrasound, activity energy expenditure by actigraphy and peak oxygen consumption and workload in an incremental exercise test. We calculated their expected values for pulse wave velocity and carotid intima media thickness and compared muscle mass and function between those with higher or lower than expected parameters. In 60 of these participants, we measured body composition sequentially to assess its change over time.

RESULTS

Age and blood pressure predicted the variance of pulse wave velocity and carotid intima media thickness with R2 values of 0.94-0.97 and 0.54 to 0.66, respectively. No differences in the frequency of sarcopenia and in muscle mass and strength were observed between participants with higher or lower than expected pulse wave velocity and carotid intima media thickness. In the group with sequential assessments, no differences in the change of muscle mass over time were observed in participants with and without accelerated vascular aging.

CONCLUSIONS

We were not able to find an association between vascular aging and sarcopenia.

Association Between Augmentation Index and Total Sleep Time in Night Shift Workers

Augmentation index and pulse wave velocity are markers of vascular compromise and independent predictors of cardiovascular risk and mortality. While the link between shift work and heightened cardiovascular risk is established, the intricate genesis of early cardiovascular outcomes in shift workers remains incompletely understood. However, there is evidence that sleep duration plays a role in this regard. Here we evaluate the association of total sleep time with pulse wave velocity, augmentation index, and central blood pressure in night shift workers. This study cross-sectionally evaluated the association of total sleep time evaluated by 10-day monitoring actigraphy with augmentation index, pulse wave velocity, and brachial and central blood pressure evaluated by oscillometry in nursing professionals, 63 shift workers (89% women; age = 45.0 ± 10.5 years), and 17 (100% women; age = 41.8 ± 15.6) day workers. There were no differences in the studied variables between shift workers and day workers. Results of correlation analysis demonstrated that pulse wave velocity, central systolic blood pressure, central diastolic blood pressure, brachial systolic blood pressure, and brachial diastolic blood pressure tended to have significant correlation with each other, while these measures did not have a significant relationship with augmentation index in both groups. However, results of adjusted restricted cubic spline analysis showed a U-shaped-curve association between total sleep time and augmentation index (p < 0.001 for trend) with a nadir at 300-360 min of total sleep time in shift workers. The present study showed that total sleep time, assessed by actigraphy, had a U-shaped association with augmentation index in shift workers, which indicated better characteristics of vascular functionality when sleep time was 5-6 h in the workers studied.

Comparison of echocardiographic aortic stiffness index measurements and pulse wave velocity measurements in obese and overweight children

BACKGROUND

Aortic/arterial stiffness is a reliable, independent predictor and a risk factor for cardiovascular mortality. Arterial stiffness is assessed by pulse wave velocity and echocardiography. The purpose of this study is to analyse aortic/arterial stiffness in patients using echocardiographic and pulse wave velocity techniques.

MATERIALS AND METHODS

The participants of this study consisted of 62 patients who presented to the Gazi University Pediatric Endocrinology and Pediatric Cardiology outpatient clinics, including 21 obese, 20 overweight, and 21 normal-weight patients. Echocardiography was performed on all patients, and echocardiographic measurements were compared to pulse wave velocity measurements.

RESULTS

The mean (min-max) arterial strain measurements were 0.146 ± 0.0 (0.06-0.3) in the obese group and 0.106 ± 0.0 (0.05-0.18) in the overweight group. In comparison to the overweight group, the obese group had greater arterial strain measurements. The pulse wave velocity measurements in the obese and overweight groups were greater than those in the normal weight group (p > 0.05). Elastic modulus and aortic stiffness ß index values were shown to be positively correlated with pulse wave velocity measurements in the obese group (r = 0.56, r = 0.53, respectively; p = 0.008, p = 0.01, respectively). Systolic and diastolic blood pressure measurements were correlated with pulse wave velocity measurements in the obese group (r = 0.98, p = 0.0001, respectively).

CONCLUSION

In our study, echocardiographic aortic measurements showing the vessel wall were correlated with pulse wave velocity measurements. Echocardiographic evaluation should be included in the routine follow-up of patients because pulse wave velocity measurement devices are not available in all centres, echocardiography is available in many centres, it is easily applicable, and it facilitates the follow-up of patients.

Arterial Stiffness and Ambulatory Blood Pressure Measurements in Children With Familial Mediterranean Fever

Familial Mediterranean fever (FMF) is an autoinflammatory disease which may cause endothelial dysfunction and arterial stiffness. In this study, we evaluated patients with FMF in terms of arterial stiffness indicators and investigated whether there was any difference according to colchicine response. This is a single-center, prospective, case-control study conducted on pediatric patients with FMF. Patients were categorized into 2 groups: patients on colchicine monotherapy (group 1) and patients who used anti-interleukin-1 (IL-1) plus colchicine (group 2). Patient age, mutations in the MEFV gene, overall duration of treatments, and general characteristics of symptoms were recorded. Laboratory values in an attack-free period were noted. Pulse wave velocity (PWV) was measured in all patients. Erythrocyte sedimentation rate and C-reactive protein, nocturnal hypertension, and PWV were higher in group 2. Arterial stiffness develops due to subclinical inflammation in patients with FMF. It is more pronounced in colchicine-resistant patients.

Vascular dysfunction in multiple sclerosis: Scoping review of current evidence for informing future research directions

BACKGROUND

The research involving vascular comorbidity in people with multiple sclerosis (MS) could be advanced through investigations applying measurements of vascular function such as pulse wave velocity or flow mediated dilation as mechanistic endpoints in the study of physical comorbidity management in MS across the lifespan. We conducted a scoping review of research on vascular function parameters and outcomes in MS and developed a research agenda for future inquiry.

METHODS

We searched PubMed from inception through February 2023 for articles involving relevant central and peripheral vascular function data or correlates of vascular function (arterial stiffness, endothelial function, blood pressure parameters, etc.) in conjunction with relevant outcomes (walking function, cognition, etc.) in MS. Studies were limited to English-language and primary research articles.

RESULTS

Our search and subsequent screening identified 10 relevant articles. Four papers focused on arterial stiffness and reported pulse wave velocity and arterial compliance in MS compared with controls. Two papers focused on endothelial function and reported flow-mediated dilation in MS compared with controls. There was evidence that arterial stiffness and endothelial function were associated with cognition and disease progression in MS, respectively. One paper reported that physical activity was associated with arterial stiffness in MS. There was one protocol paper examining the effect of a home-based exercise program on markers of subclinical atherosclerosis; however, the results are unpublished, and there was no literature beyond this surrounding the impact of lifestyle behavior (e.g., diet) or exercise interventions on vascular function.

CONCLUSION

There is emerging evidence for vascular dysfunction in MS, and this is associated with cognition and disease progression; we know very little about approaches for managing vascular dysfunction in MS. To that end, we offer an agenda for research on measurements and outcomes of vascular function in relation to MS and disease attributes, along with proposed mechanisms and lifestyle changes that could aid in managing vascular dysfunction.

Arterial stiffness and augmentation index are associated with balance function in young adults

OBJECTIVE

Arterial stiffness and pulsatile central hemodynamics have been shown to affect various aspects of physical function, such as exercise capacity, gait speed, and motor control. The aim of this study was to examine the potential association between arterial stiffness and balance function in healthy younger men and women.

METHODS

112 participants (age = 21 ± 4 years, n = 78 women) underwent measures of arterial stiffness, pulsatile central hemodynamics, balance function and physical fitness in this cross-sectional study. Postural sway was measured in triplicate while participants stood on a foam surface with their eyes closed for 20 s. The average total center of pressure path length from the three trials was used for analysis. Measures of vascular function were estimated using an oscillometric blood pressure device while at rest and included pulse wave velocity (PWV), augmentation index (AIx), and pulse pressure amplification. Measures of physical fitness used as covariates in statistical models included handgrip strength determined from a handgrip dynamometer, lower-body flexibility assessed using a sit-and-reach test, estimated maximal aerobic capacity (VO₂max) using heart rate and a step test, and body fat percentage measured from air displacement plethysmography.

RESULTS

The results from linear regression indicated that after considering sex, mean arterial pressure, body fat, estimated VO₂max, handgrip strength, and sit-and-reach, PWV (β = 0.44, p < 0.05) and AIx (β = - 0.25, p < 0.01) were significant predictors of postural sway, explaining 10.2% of the variance.

CONCLUSION

Vascular function is associated with balance function in young adults independent of physical fitness. Increased arterial stiffness may negatively influence balance, while wave reflections may be protective for balance.

Radial artery pulse wave velocity: a new characterization technique and the instabilities associated with the respiratory phase and breath-holding

Objective. Pulse wave velocity (PWV) is a key diagnostic parameter of the cardiovascular system's state. However, approaches aimed at PWV characterization often suffer from inevitable drawbacks. Statistical results demonstrating how closely PWV in the radial artery (RA) and the respiration phase correlate, as well as RA PWV evolution during breath-holding (BH), have not yet been presented in the literature. The aims of this study are (a) to propose a simple robust technique for measuring RA PWV, (b) to reveal the phase relation between the RA PWV and spontaneous breathing, and (c) to disclose the influence of BH on the RA PWV.Approach.The high-resolution remote breathing monitoring method Sorption-Enhanced Infrared Thermography (SEIRT) and the new technique aimed at measuring RA PWV described in this paper were used synchronously, and their measurement data were processed simultaneously.Main results. Spontaneous breathing leaves a synchronous 'trace' on the RA PWV. The close linear correlation of the respiration phase and the phase of concomitant RA PWV changes is statistically confirmed in five tested people (Pearson's r is of the order of 0.5-0.8, P < 0.05). The BH appreciably affects the RA PWV. A phenomenon showing that the RA PWV is not indifferent to hypoxia is observed for the first time.Significance.The proposed technique for RA PWV characterization has high prospects in biomedical diagnostics. The presented pilot study deserves attention in the context of the mutual interplay between respiratory and cardiovascular systems. It may also be useful in cases where peripheral pulse wave propagation helps assess respiratory function.

Evaluating the Arterial Stiffness as a Useful Tool in the Management of Obese Children

Childhood obesity speeds up the development of arterial stiffness and progressively increases the values of arterial pressure. The purpose of this study is to investigate the value of using pulse wave analysis (PWA) to measure arterial stiffness as a sign of vascular wall impairment in obese children. The research was focused on 60 subjects: 33 obese and 27 normal-weight. Ages ranged from 6 to 18 years old. PWA includes parameters such as pulse wave velocity (PWV), augmentation index (AIx), peripheral and central blood pressure (SBP, DBP, cSBP, cDBP), heart rate, and central pulse pressure (cPP). The device used was a Mobil-O-Graph. Blood parameters were taken from the subject's medical history, not older than 6 months. A high BMI and a large waist circumference are linked to a high PWV. The levels of LDL-c, triglycerides (TG), non-HDL-c, TG/HDL-c ratio, and total cholesterol-HDL-c ratio significantly correlate to PWV, SBP, and cSBP. Alanine aminotransferase is a reliable predictor of PWV, AIx, SBP, DBP, and cDBP, while aspartate aminotransferase is a significant predictor of AIx, mean arterial pressure (MAP), cSBP, and cPP. 25-OH-Vitamin D negatively correlates with PWV, SBP, and MAP and significantly predicts the MAP. Cortisol and TSH levels are not significant to arterial stiffness in obese children without specific comorbidities and neither is fasting glucose in obese children without impaired glucose tolerance. We conclude that PWA contributes valuable data regarding patients' vascular health and should be considered a reliable tool in the management of obese children.

Effect of vitamin K supplementation on serum calcification propensity and arterial stiffness in vitamin K-deficient kidney transplant recipients: A double-blind, randomized, placebo-controlled clinical trial

Vitamin K deficiency is common among kidney transplant recipients (KTRs) and likely contributes to progressive vascular calcification and stiffness. In this single-center, randomized, double-blind, placebo-controlled trial, we aimed to investigate the effects of vitamin K supplementation on the primary end point, serum calcification propensity (calciprotein particle maturation time, T50), and secondary end points arterial stiffness (pulse wave velocity [PWV]) and vitamin K status in 40 vitamin K-deficient KTRs (plasma dephosphorylated uncarboxylated matrix Gla protein [dp-ucMGP] ≥500 pmol/L). Participants (35% female; age, 57 ± 13 years) were randomized 1:1 to vitamin K2 (menaquinone-7, 360 μg/day) or placebo for 12 weeks. Vitamin K supplementation had no effect on calcification propensity (change in T50 vs baseline +2.3 ± 27.4 minutes) compared with placebo (+0.8 ± 34.4 minutes; P_{between group} = .88) but prevented progression of PWV (change vs baseline -0.06 ± 0.26 m/s) compared with placebo (+0.27 ± 0.43 m/s; P_{between group} = .010). Vitamin K supplementation strongly improved vitamin K status (change in dp-ucMGP vs baseline -385 [-631 to -269] pmol/L) compared with placebo (+39 [-188 to +183] pmol/L; P_{between group} < .001), although most patients remained vitamin K-deficient. In conclusion, vitamin K supplementation did not alter serum calcification propensity but prevented progression of arterial stiffness, suggesting that vitamin K has vascular effects independent of calciprotein particles. These results set the stage for longer-term intervention studies with vitamin K supplementation in KTRs. TRIAL REGISTRY: EU Clinical Trials Register (EudraCT Number: 2019-004906-88) and the Dutch Trial Register (NTR number: NL7687).

The Association Between Route of Post-menopausal Estrogen Administration and Blood Pressure and Arterial Stiffness in Community-Dwelling Women

Background

Postmenopausal hormone therapy (HT) is associated with increased cardiovascular risk. Although the route of estrogen administration may play a role in mediating risk, previous studies have not controlled for concomitant progestin use.

Objective

To investigate the association between the route of estrogen therapy (oral or non-oral) HT use, without concomitant progestin, and blood pressure and arterial stiffness in postmenopausal women.

Methods

Systolic blood pressure [SBP], diastolic blood pressure [DBP]), arterial stiffness (aortic pulse wave velocity [aPWV] and augmentation index at 75 beats per minute [AIx]) were measured using a validated automated brachial cuff-based oscillometric approach (Mobil-O-Graph) in a community-dwelling sample of 328 women.

Results

Fifty-five participants (16.8%) were ever users (current and past use) of estrogen-only HT (oral [n = 16], transdermal [n = 20], vaginal [n = 19]), and 223 were never HT users (control). Ever use of oral estrogen was associated with increased SBP and DBP (Oral: SBP: 137 ± 4 mmHg, DBP: 79 ± 2 mmHg) compared to use of non-oral estrogen (transdermal: SBP: 118 ± 2 mmHg, DBP: 73 ± 1 mmHg; p &lt; 0.01 &amp; p = 0.012, respectively; vaginal: SBP: 123 ± 2 mmHg DBP: 73 ± 2 mmHg; p = 0.02 &amp; p = 0.01, respectively.) and controls (SBP: 124 ± 1 mmHg, DBP: 74 ± 1 mmHg, p = 0.03, p = 0.02, respectively) after adjustment for covariates. aPWV was higher in oral estrogen ever users (9.9 ± 1 m/s) compared to non-oral estrogen (transdermal: 8.6 ± 0.3 m/s, p &lt; 0.01; vaginal: 8.8 ± 0.7 m/s, p = 0.03) and controls (8.9 ± 0.5 m/s, p = 0.03) but these associations were no longer significant after adjustment for covariates. AIx was higher in oral estrogen (29 ± 2 %) compared to non-oral estrogen (transdermal: 16 ± 2 %; vaginal: 22 ± 1.7 %) but this association was no longer significant after adjustment for covariates (p = 0.92 vs. non-oral; p = 0.74 vs. control).

Conclusion

Ever use of oral estrogen was associated with increased SBP and DBP compared to non-oral estrogen use and no use. Given the cardiovascular risk associated with both menopause and increased blood pressure, further studies are required exploring the potential benefits of non-oral estrogen in postmenopausal women.

Is obstructive sleep apnea associated with increased arterial stiffness in patients with COPD?

PURPOSE

To evaluate arterial stiffness, a predictor of vascular damage was assessed by means of pulse wave velocity (PWV) in patients with chronic obstructive pulmonary disease (COPD) and comorbid obstructive sleep apnea (OSA), namely overlap syndrome (OS).

METHODS

Consecutive stable patients with COPD were evaluated for OSA by means of overnight polysomnography in the laboratory. A clinical assessment was performed according to a strict protocol, including two COPD questionnaires: the COPD assessment test and the modified Medical Research Council scale. COPD severity was graded according to the guidelines of the Global Initiative for Chronic Obstructive Lung Disease. Arterial stiffness was assessed by means of PWV, using a standard technique.

RESULTS

Of 102 patients with COPD, 51 had associated OSA. The OS group had more men than the COPD group (73% vs. 47%, respectively; p < 0.01). Both groups had similar ages (66.2 ± 9.2 years vs. 69.6 ± 10.7, p = 0.09) and airflow limitation (p = 0.37). Hypertension was found in 22% of COPD patients, as opposed to 17% patients in the OS group (p = 0.29). High PWV values were present in 42% of the patients. Patients with COPD and OS had the same PWV values (9.8 vs. 10.5 m/s, p = 0.34). There were no differences in central blood pressure, peripheral blood pressure, and augmentation index between the two groups (p > 0.05).

CONCLUSION

High PWV values were frequently observed in patients with COPD. However, there was no difference in PWV between patients with OS and those with COPD alone.

Healthy Ageing and Intellectual Disability study: summary of findings and the protocol for the 10-year follow-up study

INTRODUCTION

The Healthy Ageing and Intellectual Disability (HA-ID) study is a prospective multicentre cohort study in the Netherlands that started in 2008, including 1050 older adults (aged ≥50) with intellectual disabilities (ID). The study is designed to learn more about the health and health risks of this group as they age. Compared with the amount of research in the general population, epidemiological research into the health of older adults with ID is still in its infancy. Longitudinal data about the health of this vulnerable and relatively unhealthy group are needed so that policy and care can be prioritised and for guiding clinical decision making about screening, prevention and treatment to improve healthy ageing.

METHODS AND ANALYSIS

This article presents a summary of the previous findings of the HA-ID study and describes the design of the 10-year follow-up in which a wide range of health data will be collected within five research themes: (1) cardiovascular disease; (2) physical activity, fitness and musculoskeletal disorders; (3) psychological problems and psychiatric disorders; (4) nutrition and nutritional state; and (5) frailty.

ETHICS AND DISSEMINATION

Ethical approval for the 10-year follow-up measurements of the HA-ID study has been obtained from the Medical Ethics Review Committee of the Erasmus MC, University Medical Centre Rotterdam (MEC-2019-0562).

TRIAL REGISTRATION NUMBER

This cohort study is registered in the Dutch Trial Register (NTR number NL8564) and has been conducted according to the principles of the Declaration of Helsinki.

Correlation between short-term blood pressure variability parameters with mobil-O-graph pulse wave velocity

Background

Blood pressure variability (BPV) and arterial stiffness show an association with increased cardiovascular events. Evidences demonstrated an association between higher short-term systolic BPV and stiffer arteries. There is no previous study assessed the correlation between BPV and arterial stiffness measured by a Mobil-O-Graph device. We issued to evaluate the correlation between short-term BPV parameters and Mobil-O-Graph pulse wave velocity (PWV) among suspected hypertensive individuals under treatment.

Methods

Mobil-O-Graph device estimated arterial stiffness (oscillometric PWV [oPWV]) in 649 individuals, and they recorded 24-h ambulatory BP; 428 had suspected hypertension and 221 under treatment. We analyzed the correlation between oPWV and measures of BPV: SD of 24 h BP (24-h SD), SD of daytime BP (daytime-SD), and SD of nighttime BP (nighttime-SD), weighted SD of 24-h BP (wSD), coefficient of variation of 24-h BP (CV 24-h) and average real variability (ARV).

Results

Oscillometric PWV showed a positive correlation with all systolic BPV measures, in both groups. Among suspected hypertensives: 24-h SD, r = 0.30; SD daytime-SD, r = 0.34; nighttime-SD, r = 0.16; wSD, r = 0.30; CV 24-h, r = 0.24; ARV, r = 0.22. In the treated individuals: 24-h SD, r = 0.46; daytime-SD, r = 0.47; nighttime-SD, r = 0.35; wSD, r = 0.50; CV 24-h, r = 0.43; ARV, r = 0.37, all P < 0.001. Diastolic BPV demonstrated association with some measures of BPV. In suspected hypertensive group: nighttime-SD, r = 0.13; wSD, r = 0.10, both P < 0.001. And in treated individuals: daytime-SD, r = 0.23; wSD, r = 0.22; CV 24-h, r = 0.19 (all P < 0.001), ARV, r = 0.15 (P < 0.05). Systolic daytime-SD in suspected and diastolic CV 24-h in treated group independently predicted oPWV.

Conclusion

We observed a positive and independent correlation between Mobil-O-Graph pulse wave velocity and BPV measures, strong to systolic BPV and weak to diastolic BP.

Vascular dysfunction and dyslipidemia in multiple sclerosis: are they correlated with disease duration and disability status?

BACKGROUND

There is strong evidence that vascular dysfunction is considered one of the possible causes of morbidity and mortality in patients suffering from multiple sclerosis (MS). This work aimed at assessing the arterial function and serum lipids in MS patients and correlating them with clinical and radiological findings.

RESULTS

This case-control study included 50 patients with MS and 50 age- and sex-matched controls. The arterial function was significantly reduced in MS patients, confirmed by significantly higher pulse wave velocity (PWV) and augmentation index (AIX), while the carotid IMT did not show significant difference between the two groups with no plaques in any of our patients. A significant positive correlation was found between PWV and both disease duration and disability. MS patients had significantly higher serum levels of T-cholesterol and triglycerides, and significantly lower serum levels of HDL-cholesterol, compared to controls. No significant correlation was found between serum lipids and either disease duration or disability.

CONCLUSIONS

There was a significant impairment in arterial function (assessed by the brachial cuff-based method via Mobil-O-Graph device) in MS patients compared to controls. Such impairment was significantly correlated with both disease duration and disability. MS patients had also significantly higher levels of T-cholesterol and triglycerides, compared to controls with no significant correlation between serum lipids and either disease duration or disability.

Comparing oscillometric and tonometric methods to assess pulse wave velocity: a population-based study

BACKGROUND

Oscillometric pulse wave velocity (o-PWV) represents an attractive, non invasive and non operator-dependent method to estimate arterial stiffness. Tonometric carotid-femoral measurements (cf-PWV),are considered the gold-standard for non-invasive aortic stiffness assessment. To date, no studies in the general population comparing the two methods have been performed.

METHODS AND RESULTS

1162 subjects were analysed. O-PWV and cf-PWV showed a mean difference of -0.31 m/sec(p ≤ 0.001). No significant differences between cf-PWV and o-PWVs were observed in patients without cardiovascular risk factors. The Bland and Altman analysis showed a moderate agreement between 24 h-o-PWV and cf-PWV (mean difference -0.99, LoA 4.23 to -6.22m/s). O-PWVs underestimate and overestimate arterial stiffness under and over 50 years respectively(p ≤ 0.001). Systolic blood pressure (SBP) and age differently impact cf-PWV and in office o-PWV variability (r2 0.35 and 0.88 respectively). In younger subjects a strong relationship between o-PWV and SBP reducing as age increases was found. Analysing the impact of age, an opposite trend was noticed.

CONCLUSIONS

Oscillometric PWV estimates provide reliable values in the general population. An o-PWV tendency to underestimate arterial stiffness in younger subjects and in subjects with diseases known to increase arterial stiffness and to overestimate it with increasing age was found, even if scarcely relevant in clinical perspective. Overall the present findings underline an acceptable and satisfactory agreement between oscillometric and tonometric methods for the PWV assessment. KEY MESSAGES Oscillometric and tonometric PWV estimates showed a good and satisfactory agreement in the general population, above all in subjects without cardiovascular risk factors or a documented vascular damage. In comparison with tonometric values, oscillometric PWV estimates showed, however, the tendency to underestimate arterial stiffness in younger subjects and to overestimate it with increasing age, while diverging when diseases known to increase arterial stiffness are present. The magnitude of differences in PWV estimates between tonometric and oscillometric methods found in the general population appears most likely not to be significant in everyday clinical practice.

Non-Invasive Methods for PWV Measurement in Blood Vessel Stiffness Assessment

In recent years, statistical studies highlighted an increasing incidence of cardiovascular diseases (CVD) which reflected on additional costs on the healthcare systems worldwide. Pulse wave velocity (PWV) measurement is commonly considered a CVD predictor factor as well as a marker of Arterial Stiffness (AS), since it is closely related to the mechanical characteristics of the arterial wall. An increase in PWV is due to a more rigid arterial system. Because of the prevalence of the elastic component, in young people the PWV is lower than in the elderly. Nowadays, invasive and non-invasive methods for PWV assessment are employed: there is an increasing attention in the development of non-invasive devices which mostly perform a regional PWV measurement (over a long arterial portion) rather than local (over a short arterial portion). The accepted gold-standard for non-invasive AS measurement is the carotid-femoral PWV used to evaluate the arterial damage, the corresponding cardiovascular risk and to adapt the proper therapy. This review article considers the main commercially available devices underlining their operating principles in terms of sensors, execution mode, pulse waveform acquired, site of measurement, distance and time estimation methods, as well as their main limitations in clinical practice.

An Overview of Vascular Dysfunction and Determinants: The Case of Children of African Ancestry

The balance between dilatory and constrictive factors is important as it keeps blood vessels in a homeostatic state. However, altered physiological processes as a result of obesity, hypertension, oxidative stress, and other cardiovascular risk factors may lead to vascular damage, causing an imbalance of vasoactive factors. Over time, the sustained imbalance of these vasoactive factors may lead to vascular dysfunction, which can be assessed by non-invasive methods, such as flow-mediated dilation, pulse wave velocity, flow-mediated slowing, retinal vessel analysis, peripheral vascular reactivity, and carotid intima-media thickness assessment. Although there is increasing prevalence of cardiovascular risk factors (obesity and hypertension) in children in sub-Saharan Africa, little is known about how this may affect vascular function. This review focuses on vasoactive factors implicated in vascular (dys)function, highlighting the determinants and consequences of vascular dysfunction. It further describes the non-invasive methods used for vascular (dys)function assessments and, last, describes the impact of cardiovascular risk factors on vascular dysfunction in children of African ancestry.

Associations of Sex Hormones and Hormonal Status With Arterial Stiffness in a Female Sample From Reproductive Years to Menopause

OBJECTIVE

Loss of sex hormones has been suggested to underlie menopause-associated increment in cardiovascular risk. We investigated associations of sex hormones with arterial stiffness in 19-58-years-old women. We also studied associations of specific hormonal stages, including natural menstrual cycle, cycle with combined oral contraceptives (COC) and menopausal status with or without hormone therapy (HT), with arterial stiffness.

METHODS

This study includes repeated measurements of 65 healthy women representing reproductive (n=16 natural, n=10 COC-users) and menopause (n=5 perimenopausal, n=26 postmenopausal, n=8 HT-users) stages. Arterial stiffness outcomes were aortic pulse wave velocity (PWVao) and augmentation index (AIx%) assessed using Arteriograph-device. Generalized estimating equation models were constructed to investigate associations of each hormone (wide age-range models) or hormonal stage (age-group focused models) with arterial stiffness. PWVao models with cross-sectional approach, were adjusted for age, relative fitness, fat mass and mean arterial pressure, while models with longitudinal approach were adjusted for mean arterial pressure. AIx% models used the same approach for adjustments and were also adjusted for heart rate.

RESULTS

Negative and positive associations with arterial stiffness variables were observed for estradiol and follicle-stimulating hormone, respectively, until adjustment for confounding effect of age. In naturally menstruating women, AIx% was higher at ovulation (B=3.63, p<0.001) compared to the early follicular phase. In COC-users, PWVao was lower during active (B=-0.33 - -0.57, p<0.05) than inactive pills. In menopausal women, HT-users had higher PWVao (B=1.43, p=0.03) than postmenopausal non-HT-users.

CONCLUSIONS

When using wide age-range assessments covering reproductive to menopausal lifespan it is difficult to differentiate age- and hormone-mediated associations, because age-mediated influence on arterial stiffness seemed to overrule potential hormone-mediated influences. However, hormonal status associated differentially with arterial stiffness in age-group focused analyses. Thus, the role of sex hormones cannot be excluded. Further research is warranted to resolve potential hormone-mediated mechanisms affecting arterial elasticity.

A Randomized, Double-Blind, Placebo-Controlled Clinical Trial of an Omega-3 Fatty Acid Supplement in Patients With Predialysis Chronic Kidney Disease

OBJECTIVE

Omega-3 fatty acids may reduce albuminuria and cardiovascular risk factors in patients with chronic kidney disease (CKD). We aimed to assess the effects of omega-3 fatty acid supplementation on albuminuria, blood pressure, pulse wave velocity, and inflammatory markers in patients with CKD.

METHODS

Patients with CKD and a urine albumin excretion of at least 30 mg/g creatinine were supplemented for 3 months with 3,666 mg/day of docosahexaenoic and eicosapentaenoic acids or a corn oil supplement. The study was double blind. At baseline, 6 weeks, and 12 weeks, fasting blood and morning spot urine samples were obtained. Blood pressure, carotid intima media thickness, and pulse wave velocity were measured. The main outcome measure was a reduction of ≥20% in urine albumin.

RESULTS

One hundred patients were randomized (50 received omega-3 fatty acids and 50 received corn oil). Four patients who received omega-3 fatty acids and 5 who received vegetable oil were lost to follow-up. In patients receiving omega-3 fatty acids, the omega-3 index increased from 3.08 (2.32-3.81) to 5.48 (3.045-7.04) percent. A 20% reduction in urine albumin excretion was observed in 13 participants of the control group and 19 participants of omega-3 group (Fisher's exact P = .274). However, the supplement had a significant and positive effect on pulse wave velocity and triglyceride level.

CONCLUSION

An omega-3 fatty acid supplement of 3,666 mg/day did not modify urine albumin excretion in patients with CKD but did improve pulse wave velocity and serum triglyceride levels.

Changes in Central 24-h Ambulatory Blood Pressure and Hemodynamics 12 Months After Bariatric Surgery: the BARIHTA Study

BACKGROUND

Weight loss is associated to blood pressure (BP) reduction in obese patients. There is no information on central 24-h BP changes after bariatric surgery (BS).

METHODS AND RESULTS

In this study, we analyzed changes in 24-h BP 12 months following BS, with intermediate evaluations at 1, 3, and 6 months, in severely obese adults. The primary endpoint was aortic (central) 24-h systolic BP changes. Circadian BP patterns and hypertension resolution were also assessed. As secondary endpoints, we analyze changes in central 24-h diastolic BP as well as in all office and ambulatory peripheral BP parameters. Obese adults scheduled for BS as routine clinical care were recruited. We included 62 patients (39% with hypertension, 77% women, body mass index, 42.6 ± 5.5 kg/m²). Reduction in body weight was mean (IQR) 30.5% (26.2-34.4) 1 year after BS. Mean (95% CI) change in central 24-h systolic BP was - 3.1 mmHg (- 5.5 to - 0.7), p = 0.01 after adjustment for age, sex, and baseline hypertensive status. BP parameter changes were different between normotensives and hypertensives. Mean (95% CI) change in central 24-h systolic BP was - 5.2 mmHg (- 7.7 to - 2.7), p < 0.001, in normotensives and - 0.5 mmHg (- 5.1 to 4.0), p = 0.818, in hypertensives. There was a remission of hypertension in 48% of patients. Most patients had a reduced dipping pattern, similarly at baseline and 12 months after BS.

CONCLUSIONS

Among patients with severe obesity, there was a substantial central 24-h systolic BP decrease 12 months following BS. Importantly, this change was observed in those patients with normal BP at baseline.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03115502.

Reference values of office central blood pressure, pulse wave velocity, and augmentation index recorded by means of the Mobil-O-Graph PWA monitor

Assessment of central blood pressure (BP), pulse wave velocity (PWV), and augmentation index (AIx) measurements may improve cardiovascular risk stratification. This study aimed to establish reference office values for central BP, PWV, and AIx by means of a Mobil-O-Graph PWA monitor and to evaluate the impact of cardiovascular risk factors (CVRFs) on these measurements. We cross-sectionally evaluated clinical characteristics, central BP, PWV, AIx, and peripheral BP measurements among 867 apparently healthy individuals (age = 46.0 ± 15.5 years, 39% males) who were free of obesity, hypertension, active smoking, dyslipidemia, and diabetes (CVRF-No) and 5632 individuals (age = 57.0 ± 14.7 years, 44% males) with at least one of these major CVRFs (CVRF-Yes). Reference values for central BP, PWV, and AIx were provided for the CVRF-No and CVRF-Yes groups, stratified by age and sex. PWV and AIx exhibited curvilinear increases with age, and there was an interaction between age and sex for central systolic BP and PWV in both the CVRF-No and CVRF-Yes groups. The results of a multivariable analysis including the whole sample (n = 6499) showed that obesity had a direct association with central BP, while diabetes was directly related to PWV. In addition, alcohol intake was directly associated with central BP, while performance of physical activity was inversely related to AIx. In conclusion, values of office-measured central BP, PWV, and AIx obtained in an apparently healthy population and in a population with CVRFs are now available according to age and sex and may be useful to build thresholds for use in clinical practice.

Association of impaired arterial wall properties with the presence of coronary artery disease in patients with abdominal aortic aneurysms

Pulse wave velocity (PWV) is a valid, clinically feasible marker of arterial stiffening, and a strong predictor of outcomes. The present study aimed to compare aortic elastic properties in patients with abdominal aortic aneurysms (AAA), with or without coronary artery disease (CAD), as well as healthy individuals. A total of 130 patients with AAA, eligible for interventional repair, and 30 healthy individuals, comprising the control group (HC), were enrolled. Presence of CAD was identified by coronary angiography. Aortic PWV (aPWV) was measured using the Arteriograph. aPWV was found considerably higher in AAA patients compared with HC group (11.5 ± 2.9 vs 7.3 ± 1.6 m/s, P < .001). Importantly, among patients with AAA, those with concomitant CAD (n = 41) had greater aPWV than those without CAD (12.5 ± 2.9 vs 11.0 ± 3.0 m/s, P = .03). In receiver operator curve (ROC) analysis, a value of aPWV above 12.8 m/s was identified to correlate with the presence of CAD in the AAA patient population. After adjustment for confounders, including hypertension which is one of the major risk factors for abdominal aneurysms, multivariate logistic regression analysis revealed that this aPWV cutoff remained independently associated with presence of CAD [odds ratio = 1.64, 95% confidence interval =1.19-4.08, P = .03]. The coexistence of CAD and AAA is characterized by a greater arterial stiffness. This finding should be taken into consideration when selecting endovascular stents with more favorable elastic properties. Moreover, AAA patients with high aPWV (>12.8 m/s) are more likely to also have CAD, and this may be considered by vascular surgeons when evaluating patients' cardiovascular risk.

Short-term reproducibility of the 24-h ambulatory monitoring of brachial and central hemodynamics in untreated Chinese

Objective: Advanced technology allows non-invasive monitoring of the 24-h brachial and central hemodynamics simultaneously. However, related reproducibility data was limited in White patients. We therefore explored if the novel measurements would be reproducible in Chinese. Methods: From February 2017 to January 2018, 152 untreated patients who were suspected of hypertension and referred for ambulatory blood pressure (BP) monitoring were recruited. Ambulatory BP monitoring was repeated within one month (median, 12.5 days) using the Mobil-O-Graph monitors (IEM, Germany). Reproducibility was assessed as the intra-class correlation coefficient (ICC), coefficient of variation (CV), and repeatability coefficient (RC). Results: The 152 participants (average age, 58.6 years) included 54 men and 98 women. The first and second means of the ambulatory brachial and central BPs, pulse wave velocity (PWV), augmentation pressure, augmentation index (AIx) and AIx at a heart rate of 75 beats per minute (AIx@75) were all similar (p ≥ 0.065), except that the repeated daytime and 24-h brachial and central systolic BPs and pulse pressure slightly differed by approximately 1-2 mmHg (p ≤ 0.011). ICC ranged from 0.70 to 0.94 for all ambulatory BPs and ≥0.91 for the arterial measurements. CV was in the range from 5.0% to 10.3% for all BPs and PWV measurements, and from 15.5% to 22.3% for AIx and AIx@75. RC expressed as percentages of maximal variation was <15% for the PWVs and ranged from 25.5% to 54.7% for BPs, AIx and AIx@75. Conclusions: The 24-h ambulatory brachial and central BPs and arterial measurements were reproducible within a short time period in Chinese, and could therefore be used in clinical practice and research settings.