Regional pulse-wave velocity in the arterial tree.

Abstract Context: Insulin reportedly impairs endothelial function in conduit arteries but improves it in resistance and microvascular arterioles in healthy humans. No studies have assessed endothelial function at three arterial levels in healthy or metabolic syndrome (METSYN) subjects. Objective: The objective of the study was to compare endothelial responsiveness of conduit arteries, resistance, and microvascular arterioles to insulin in healthy and METSYN subjects. Design: We assessed conduit, resistance, and microvascular arterial function in the postabsorptive and postprandial states and during euglycemic hyperinsulinemia (insulin clamp). Setting: The study was conducted at a clinical research unit. Participants: Age-matched healthy and METSYN subjects participated in the study. Interventions: We used brachial flow-mediated dilation, forearm postischemic flow velocity, and contrast-enhanced ultrasound to assess the conduit artery, resistance arteriole, and microvascular arteriolar endothelial function, respectively. We also assessed the conduit artery stiffness (pulse wave velocity and augmentation index) and measured the plasma concentrations of 92 cardiovascular disease biomarkers at baseline and after the clamp. Results: Postabsorptive and postprandial endothelial function was similar in controls and METSYN in all tested vessels. METSYN subjects were metabolically insulin resistant (P < .005). In controls, but not METSYN subjects, during euglycemic hyperinsulinemia, endothelial function improved at each level of arterial vasculature (P < .05 or less for each). Conduit vessel stiffness (pulse wave velocity) was increased in the METSYN group. Twelve of 92 biomarkers differed at baseline (P < .001) and remained different at the end of the insulin clamp. Conclusions: We conclude that insulin enhances arterial endothelial function in health but not in METSYN, and this vascular insulin resistance may underlie its increased cardiovascular disease risk.

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Maternal arterial stiffness in pregnancies affected by preeclampsia

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.01106.2008 ◽

2009 ◽

Vol 297 (2) ◽

pp. H759-H764 ◽

Cited By ~ 61

Author(s):

Christina Kaihura ◽

Makrina D. Savvidou ◽

James M. Anderson ◽

Carmel M. McEniery ◽

Kypros H. Nicolaides

Keyword(s):

Arterial Stiffness ◽

Pulse Wave Velocity ◽

Wave Velocity ◽

Wave Reflection ◽

Pulse Wave ◽

Augmentation Index ◽

Applanation Tonometry ◽

Control Group ◽

Arterial Tree ◽

Cross Sectional

Preeclampsia (PE) is characterized by an aberrant maternal cardiovascular adaptation to pregnancy and increased cardiovascular risk later on in life. The aim of this study was to compare the maternal wave reflections and arterial stiffness in women with established PE and those with normotensive pregnancies, after systematic adjustment for known confounders. This was a cross-sectional study involving 69 normotensive, pregnant women and 54 women with established PE. Maternal wave reflection (augmentation index) and pulse wave velocity of the carotid-radial and carotid-femoral parts of the arterial tree were assessed noninvasively using applanation tonometry. The measurements were adjusted for maternal age, heart rate, mean arterial pressure, and aortic time to wave reflection and expressed as multiples of the median (MoM) of the control group. In the PE group, compared with controls, there was an increase in the median pulse wave velocity of both the carotid to femoral [1.1, interquartile rage (IQR) 1.0–1.3 MoM vs. 0.9, IQR 0.9–1.0 MoM; P < 0.0001] and carotid to radial (1.0, IQR 0.9–1.1 MoM vs. 0.9, IQR 0.9–1.0 MoM; P = 0.01) parts of the arterial tree. In contrast, there were no significant differences between the two groups in the median augmentation index (0.9, IQR 0.7–1.1 MoM vs. 1.0, IQR 0.5–1.8 MoM; P = 0.46). In conclusion, we found that established PE is characterized by increased maternal arterial stiffness but not altered maternal wave reflection.

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Radial-Digital pulse wave velocity: a non-invasive method for assessing stiffness of small conduit arteries.

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00551.2020 ◽

2021 ◽

Author(s):

Hasan Obeid ◽

Catherine Fortier ◽

Charles-Antoine Garneau ◽

Mathilde Paré ◽

Pierre Boutouyrie ◽

...

Keyword(s):

Numerical Simulation ◽

Hydrostatic Pressure ◽

Pulse Wave Velocity ◽

Wave Velocity ◽

Pulse Wave ◽

Second Derivative ◽

Tree Model ◽

Arterial Tree ◽

Non Invasive ◽

Digital Pulse

Background: Pulse wave velocity (PWV) is used to evaluate regional stiffness of large and medium-sized arteries. Here, we examine the feasibility and reliability of radial-digital PWV (RD-PWV) as a measure of regional stiffness of small conduit arteries, and its response to changes in hydrostatic pressure. Methods and results: In 29 healthy subjects, we used Complior Analyse piezoelectric probes to record arterial pulse wave at radial artery and tip of the index. We determined transit time by second-derivative and intersecting-tangents using the device-embedded algorithms, in house Matlab-based analyses of only reliable waves, and by numerical simulation using a one dimensional (1-D) arterial tree model coupled with heart model. Second-derivative RD-PWV were 4.68±1.18, 4.69±1.21, 4.32±1.19 m/s for device-embedded, Matlab-based and numerical simulation analyses, respectively. Intersecting-tangents RD-PWV were 4.73±1.20, 4.45±1.08, 4.50±0.84 m/s for device-embedded, Matlab-based and numerical simulation analyses, respectively. Intersession coefficients of variation were 7.0±4.9% and 3.2±1.9% (P=0.04) for device-embedded and Matlab-based second derivative algorithms. In 15 subjects, we examine the response of RD-PWV to changes in local hydrostatic pressure by vertical displacement of the hand. For an increase of 10 mm Hg in local hydrostatic pressure RD-PWV increased by 0.28 m/s (95% CI: 0.16 to 0.40; P<0.001). Conclusions: This study shows that RD-PWV can be used for the non-invasive assessment of regional stiffness of small conduit arteries. This finding allows for an integrated approach for assessing arterial stiffness gradient from aorta, to medium-sized arteries, and now to small conduit arteries.

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Arterial viscoelasticity: role in the dependency of pulse wave velocity on heart rate in conduit arteries

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00849.2016 ◽

2017 ◽

Vol 312 (6) ◽

pp. H1185-H1194 ◽

Cited By ~ 20

Author(s):

Hanguang Xiao ◽

Isabella Tan ◽

Mark Butlin ◽

Decai Li ◽

Alberto P. Avolio

Keyword(s):

Heart Rate ◽

Pulse Wave Velocity ◽

Transmission Line ◽

Wave Velocity ◽

Pulse Wave ◽

Large Artery ◽

Transmission Line Model ◽

Arterial Tree ◽

Line Model ◽

Physiological Studies

Experimental investigations have established that the stiffness of large arteries has a dependency on acute heart rate (HR) changes. However, the possible underlying mechanisms inherent in this HR dependency have not been well established. This study aimed to explore a plausible viscoelastic mechanism by which HR exerts an influence on arterial stiffness. A multisegment transmission line model of the human arterial tree incorporating fractional viscoelastic components in each segment was used to investigate the effect of varying fractional order parameter (α) of viscoelasticity on the dependence of aortic arch to femoral artery pulse wave velocity (afPWV) on HR. HR was varied from 60 to 100 beats/min at a fixed mean flow of 100 ml/s. PWV was calculated by intersecting tangent method (afPWVTan) and by phase velocity from the transfer function (afPWVTF) in the time and frequency domain, respectively. PWV was significantly and positively associated with HR for α ≥ 0.6; for α = 0.6, 0.8, and 1, HR-dependent changes in afPWVTan were 0.01 ± 0.02, 0.07 ± 0.04, and 0.22 ± 0.09 m/s per 5 beats/min; HR-dependent changes in afPWVTF were 0.02 ± 0.01, 0.12 ± 0.00, and 0.34 ± 0.01 m/s per 5 beats/min, respectively. This crosses the range of previous physiological studies where the dependence of PWV on HR was found to be between 0.08 and 0.10 m/s per 5 beats/min. Therefore, viscoelasticity of the arterial wall could contribute to mechanisms through which large artery stiffness changes with changing HR. Physiological studies are required to confirm this mechanism. NEW & NOTEWORTHY This study used a transmission line model to elucidate the role of arterial viscoelasticity in the dependency of pulse wave velocity on heart rate. The model uses fractional viscoelasticity concepts, which provided novel insights into arterial hemodynamics. This study also provides a means of assessing the clinical manifestation of the association of pulse wave velocity and heart rate.

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Immediate variations in pulse wave velocity caused by Adrenalin in short, uniform parts of the arterial tree

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1959.197.2.432 ◽

1959 ◽

Vol 197 (2) ◽

pp. 432-436 ◽

Cited By ~ 5

Author(s):

James C. Kraner ◽

Eric Ogden ◽

Richard C. McPherson

Keyword(s):

Blood Pressure ◽

Pulse Wave Velocity ◽

Diastolic Blood Pressure ◽

Wave Velocity ◽

Pulse Wave ◽

Marked Decrease ◽

Velocity Measurements ◽

Arterial Tree ◽

Average Value ◽

Anesthetized Dogs

Pulse wave velocity measurements confined to a 6–9-cm segment of the femoral artery in eight anesthetized dogs gave an average value of 7.8 m/sec. The velocity varies with the diastolic blood pressure. This was particularly noticeable in one dog which showed marked spontaneous variations of diastolic blood pressure from beat to beat. The response to Adrenalin was diphasic showing first an increase in pulse wave velocity and then a marked decrease without a corresponding decrease in diastolic blood pressure. This observation suggests a physical change in the artery compatible with relaxation of the smooth muscle, rather than contraction.

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Impact of Cardiovascular Factors on Pulse Wave Velocity and Total Vascular Resistance in Different Age Group Patients with Cardiovascular Disorders

Current Aging Science ◽

10.2174/1874609812666190226151500 ◽

2019 ◽

Vol 11 (4) ◽

pp. 261-268 ◽

Cited By ~ 2

Author(s):

Amit Ghosh ◽

Abhijith Dharmarajan ◽

Prafulla K. Swain ◽

Debasish Das ◽

Poonam Verma ◽

...

Keyword(s):

Blood Pressure ◽

Arterial Stiffness ◽

Pulse Wave Velocity ◽

Wave Velocity ◽

Vascular Resistance ◽

Pulse Wave ◽

Negative Impact ◽

Age Group ◽

Arterial Tree ◽

Cardiovascular Morbidity And Mortality

Background: Pulse Wave Velocity (PWV) is the propagation speed of the wave-induced along the aorta and arterial tree, each time the heart beats. PWV increases with increased arterial stiffness, thus establishing it as a reliable prognostic marker for cardiovascular morbidity and mortality. On the other hand, Total Vascular Resistance (TVR) is the overall resistance offered by systemic circulation and pulmonary circulation. This resistance needs to be overcome in order to create the flow of blood through the circulatory system. The goal of this study was to investigate the influence of different cardiovascular factors on arterial stiffness and vascular resistance in CVD patient from eastern India population. Methods: Total of 782 patients with Cardiovascular Disease (CVD) like hypertension, Ischemic heart disease, Congestive cardiac failure and peripheral arterial disease were included to evaluate the cardiovascular hemodynamic and non-hemodynamic parameter by oscillometric method and investigated those factors on PWV and TVR in subjects of both sexes aged between 15 to 87 years. Results: The old age (> 55 years) was found to have greatest impact on PWV as compared with younger age group. Systolic Blood Pressure (SBP), Heart Rate (HR), augmentation pressure and Body Surface Area (BSA) had a positive association with the PWV. Augmentation Index and Body Mass Index (BMI) had a negative impact on the PWV. Conclusion: Despite the limitations, like unequal number of male and female participants, wide variation of the age of the subjects and analyzing association of many factors at a time, our large and community-based study show individual blood pressure and pulse pressure depending on complex interaction between large arteries and arterioles. This study sheds light on the relationship between proximal and distal part (PWV and TVR) of the arterial tree as well as their association with different hemodynamic and non-hemodynamic parameters.

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