Measuring Blood Pulse Wave Velocity with Bioimpedance in Different Age Groups

In this project, we have studied the use of electrical impedance cardiography as a possible method for measuring blood pulse wave velocity, and hence be an aid in the assessment of the degree of arteriosclerosis. Using two different four-electrode setups, we measured the timing of the systolic pulse at two locations, the upper arm and the thorax, and found that the pulse wave velocity was in general higher in older volunteers and furthermore that it was also more heart rate dependent for older subjects. We attribute this to the fact that the degree of arteriosclerosis typically increases with age and that stiffening of the arterial wall will make the arteries less able to comply with increased heart rate (and corresponding blood pressure), without leading to increased pulse wave velocity. In view of these findings, we conclude that impedance cardiography seems to be well suited and practical for pulse wave velocity measurements and possibly for the assessment of the degree of arteriosclerosis. However, further studies are needed for comparison between this approach and reference methods for pulse wave velocity and assessment of arteriosclerosis before any firm conclusions can be drawn.

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Interaction of aortic and carotid sinus baroreceptors: effect of activation times

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1975.228.1.238 ◽

1975 ◽

Vol 228 (1) ◽

pp. 238-243 ◽

Cited By ~ 5

Author(s):

PG Katona ◽

KS Tan

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Electrical Stimulation ◽

Pulse Wave Velocity ◽

Wave Velocity ◽

Pulse Wave ◽

Carotid Sinus ◽

Relative Timing ◽

Relative Delay ◽

Activation Times

Changes in pulse-wave velocity were simulated by changing the relative timing between aortic and carotid sinus barorecptor activity in anesthetized rabbits and dogs. In the rabbit, electrical stimulation was used to vary the timing; in the dog, it was also varied by perfusing the carotid sinuses with externally generated pressure pulses that could be triggered in any portion of the cardiac cycle. Changing the relative delay between aortic and carotid sinsus nerve stimulation did not result in variations of blood pressure or heart rate in the rabbit. Varing the time of electrical stimulation of the carotid sinus nerve caused at most 5 mmHg change of blood pressure in the dog. Delay-related heart-rate changes could be usually observed only when the stimulus consisted of short, high-intensity bursts. When the carotid sinus was externally perfused with pulses of pressure, only one out of five dogs showed delay-related variations in blood pressure (3mmHg) and heart rate (6 beats/min). It is concluded that variations in pulse-wave velocity are unlikely to play a significant role in acute cardiovascular control.

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Differential Associations for Salivary Sodium, Potassium, Calcium, and Phosphate Levels with Carotid Intima Media Thickness, Heart Rate, and Arterial Stiffness

Disease Markers ◽

10.1155/2018/3152146 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

Carlos Labat ◽

Silke Thul ◽

John Pirault ◽

Mohamed Temmar ◽

Simon N. Thornton ◽

...

Keyword(s):

Heart Rate ◽

Cardiovascular Risk ◽

Pulse Wave Velocity ◽

Wave Velocity ◽

Risk Evaluation ◽

Pulse Wave ◽

Intima Media Thickness ◽

Sodium Potassium ◽

Media Thickness ◽

Salivary Electrolytes

Salivary biomarkers may offer a noninvasive and easy sampling alternative in cardiovascular risk evaluation. The aim of the present study was to establish associations of salivary potassium, sodium, calcium, and phosphate levels with the cardiovascular phenotype determined by carotid ultrasound and carotid-femoral pulse wave velocity and to identify possible covariates for these associations. N=241 samples of nonstimulated whole buccal saliva were obtained from subjects with (n=143; 59%) or without (n=98; 41%) hypertension. The potassium concentrations were 10-fold higher in saliva compared with plasma, whereas sodium concentrations exhibited the reverse relation between saliva and blood. There were no significant correlations between the levels of sodium, potassium, or calcium in saliva and plasma. All salivary electrolytes, except sodium, were significantly associated with age. In age-adjusted analyses, salivary potassium was significantly associated with carotid artery intima media thickness (cIMT) and carotid-femoral pulse wave velocity, and these associations were at the limit of significance in multivariate analyses including prevalent cardiovascular disease and risk factors. Body mass index was a significant confounder for salivary potassium. Salivary phosphate was significantly associated with cIMT in the multivariate analysis. Salivary potassium, calcium, and phosphate levels were significantly associated with heart rate in the univariate age-adjusted as well as in two different multivariate models, whereas no significant associations between sodium and heart rate were observed. In conclusion, the differential association of salivary electrolytes with cardiovascular phenotypes indicates that these electrolytes should be further studied for their predictive value as noninvasive biomarkers for cardiovascular risk evaluation.

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