scholarly journals The effect of stepwise changes in paced heart rate on cardiac output, arterial blood pressure and arterial properties as measured by systemic arterial compliance and pulse wave velocity

2002 ◽  
Vol 15 (4) ◽  
pp. A67 ◽  
Author(s):  
C GATZKA
2020 ◽  
Vol 25 (12) ◽  
pp. 4036
Author(s):  
H. Yilmaz Ak ◽  
Y. Ozsahin ◽  
N. Baskurt Aladag ◽  
F. Gencoglu ◽  
B. Sahin Yildiz ◽  
...  

Aim. Patients with chronic inflammatory diseases (CID), such as rheumatoid arthritis (RA) and familial Mediterranean fever (FMF) are more likely to have higher risk of cardiac events. Pulse wave velocity (PWV) can be used to measure the aortic dis-tensibility and it is known as inversely related to the arterial compliance. Increased aortic stiffness which is assessed by PWV, is seem to be associated with arterial blood pressure. In this study, we investigated the arterial compliance by PWV in patients with CID including RA and FMF.Material and methods. We studied 25 patients with RA, 33 patients with FMF and 31 healthy subjects without a history of any cardiovascular risk factors such as hypertension, diabetes mellitus, hyperlipidaemia (89 subjects in total). We measured the arterial compliance by automatic carotid-femoral (aortic) PWV using Complior Colson (France) device. PWV (m/s) = distance (m)/transit time(s).Results. It is seen that, patients with CID have higher carotid-femoral (aortic) PWV (8,76±2,09 vs 8,07±0,94 m/s) compared to control groups (p=0,03). There were significant correlations between PWV and age, body-mass index, systolic blood pressure, diastolic blood pressure and mean blood pressure. (p<0,001, r=0,65; p<0,001, r=0,36; p<0,001, r=0,42; p<0,001, r=0,46; p<0,001, r=0,48, respectively).Conclusion. Arterial compliance, which is assessed by carotid-femoral (aortic) PWV, is decreased in patients with CID such as RA and FMF when it is compared to healthy control group.


Pulse ◽  
2016 ◽  
Vol 4 (4) ◽  
pp. 175-179 ◽  
Author(s):  
Sara V. Greve ◽  
Stephan Laurent ◽  
Michael H. Olsen

1975 ◽  
Vol 228 (1) ◽  
pp. 238-243 ◽  
Author(s):  
PG Katona ◽  
KS Tan

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.


1999 ◽  
Vol 277 (2) ◽  
pp. H576-H583 ◽  
Author(s):  
José González-Alonso ◽  
Ricardo Mora-Rodríguez ◽  
Edward F. Coyle

We determined whether the deleterious effects of dehydration and hyperthermia on cardiovascular function during upright exercise were attenuated by elevating central blood volume with supine exercise. Seven trained men [maximal oxygen consumption (V˙o 2 max) 4.7 ± 0.4 l/min (mean ± SE)] cycled for 30 min in the heat (35°C) in the upright and in the supine positions (V˙o 2 2.93 ± 0.27 l/min) while maintaining euhydration by fluid ingestion or while being dehydrated by 5% of body weight after 2 h of upright exercise. When subjects were euhydrated, esophageal temperature (Tes) was 37.8–38.0°C in both body postures. Dehydration caused equal hyperthermia during both upright and supine exercise (Tes = 38.7–38.8°C). During upright exercise, dehydration lowered stroke volume (SV), cardiac output, mean arterial pressure (MAP), and cutaneous vascular conductance and increased heart rate and plasma catecholamines [30 ± 6 ml, 3.0 ± 0.7 l/min, 6 ± 2 mmHg, 22 ± 8%, 14 ± 2 beats/min, and 50–96%, respectively; all P < 0.05]. In contrast, during supine exercise, dehydration did not cause significant alterations in MAP, cutaneous vascular conductance, or plasma catecholamines. Furthermore, supine versus upright exercise attenuated the increases in heart rate (7 ± 2 vs. 9 ± 1%) and the reductions in SV (13 ± 4 vs. 21 ± 3%) and cardiac output (8 ± 3 vs. 14 ± 3%) (all P< 0.05). These results suggest that the decline in cutaneous vascular conductance and the increase in plasma norepinephrine concentration, independent of hyperthermia, are associated with a reduction in central blood volume and a lower arterial blood pressure.


1995 ◽  
Vol 78 (5) ◽  
pp. 1793-1799 ◽  
Author(s):  
M. Kamitomo ◽  
T. Ohtsuka ◽  
R. D. Gilbert

We exposed fetuses to high-altitude (3,820 m) hypoxemia from 30 to 130 days gestation, when we measured fetal heart rate, right and left ventricular outputs with electromagnetic flow probes, and arterial blood pressure during an isoproterenol dose-response infusion. We also measured the distribution of cardiac output with radiolabeled microspheres during the maximal isoproterenol dose. Baseline fetal arterial blood pressure was higher in long-term hypoxemic fetuses (50.1 +/- 1.3 vs. 43.4 +/- 1.0 mmHg) but fell during the isoproterenol infusion to 41.3 +/- 1.4 and 37.5 +/- 1.4 mmHg, respectively, at the highest dose. Heart rate was the same in both groups and did not differ during isoproterenol infusion. Baseline fetal cardiac output was lower in the hypoxemic group (339 +/- 18 vs. 436 +/- 19 ml.min-1.kg-1) due mainly to a reduction in right ventricular output. During the isoproterenol infusion, right ventricular output increased to the same extent in both hypoxemic and normoxic fetuses (approximately 35%); however, left ventricular output increased only approximately 15% in the hypoxemic group compared with approximately 40% in the normoxic group. The percent change in individual organ blood flows during isoproterenol infusion in the hypoxemic groups was not significantly different from the normoxic group. All of the mechanisms that might be responsible for the differential response of the fetal left and right ventricles to long-term hypoxia are not understood and need further exploration.


1991 ◽  
Vol 260 (1) ◽  
pp. H254-H259
Author(s):  
R. Maass-Moreno ◽  
C. F. Rothe

We tested the hypothesis that the blood volumes of the spleen and liver of cats are reflexly controlled by the carotid sinus (CS) baroreceptors. In pentobarbital-anesthetized cats the CS area was isolated and perfused so that intracarotid pressure (Pcs) could be controlled while maintaining a normal brain blood perfusion. The volume changes of the liver and spleen were estimated by measuring their thickness using ultrasonic techniques. Cardiac output, systemic arterial blood pressure (Psa), central venous pressure, central blood volume, total peripheral resistance, and heart rate were also measured. In vagotomized cats, increasing Pcs by 100 mmHg caused a significant reduction in Psa (-67.8%), cardiac output (-26.6%), total peripheral resistance (-49.5%), and heart rate (-15%) and significantly increased spleen volume (9.7%, corresponding to a 2.1 +/- 0.5 mm increase in thickness). The liver volume decreased, but only by 1.6% (0.6 +/- 0.2 mm decrease in thickness), a change opposite that observed in the spleen. The changes in cardiovascular variables and in spleen volume suggest that the animals had functioning reflexes. These results indicate that in pentobarbital-anesthetized cats the carotid baroreceptors affect the volume of the spleen but not the liver and suggest that, although the spleen has an active role in the control of arterial blood pressure in the cat, the liver does not.


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