Spontaneous diameter oscillations of the radial artery in humans

Hayoz, Daniel; Tardy, Yves; Rutschmann, B.; Mignot, J; Achakri, H.; Feihl, François; Meister, Jean-Jacques; Waeber, Bernard; Brunner, H.

doi:10.1152/ajpheart.1993.264.6.h2080

Cited by 47 publications

(34 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1B): mechanical indices independent of carotid atherosclerosis 15) . High stretch stimulus and shear stress seem to play important roles in carotid atherosclerosis, which are reflected by mechanical indices; however, there are limitations in assessing mechanical stress [16][17][18] . Since the arterial wall is not homogeneous, parameters such as β-stiffness assume that homogeneity of the wall may be unrealistic and inaccurate.…”

Section: Transthoracic Echocardiography and Carotid Ultrasonographymentioning

confidence: 99%

Validation of Circumferential Carotid Artery Strain as a Screening Tool for Subclinical Atherosclerosis

Park

Cho

Kim

et al. 2012

JAT

View full text Add to dashboard Cite

show abstract

Section: Transthoracic Echocardiography and Carotid Ultrasonographymentioning

confidence: 99%

Validation of Circumferential Carotid Artery Strain as a Screening Tool for Subclinical Atherosclerosis

Park

Cho

Kim

et al. 2012

JAT

View full text Add to dashboard Cite

show abstract

“…Another possible source of variability is the spontaneous oscillations in diameter and distensibility known to occur in the human radial artery. 23 Catheterization patients were unstable. Many of the patients had been sedated and some were undoubtedly anxious, resulting in respiratory variations in aortic pressures.…”

Section: Smulyan Et Al Calculated Aortic Pulses 153mentioning

confidence: 99%

Clinical Utility of Aortic Pulses and Pressures Calculated From Applanated Radial-Artery Pulses

et al. 2003

View full text Add to dashboard Cite

Abstract-Brachial artery cuff blood pressures are but approximations of central aortic pressures. The actual pressures against which the left ventricle must pump would be useful clinical information if obtained noninvasively. Our aim was to determine the clinical utility of aortic pulses and pressures calculated from noninvasively obtained radial-artery pulses. Radial-arterial pulses were recorded by applanation and calibrated with arm/cuff oscillometric pressures. Aortic pulses and pressures were calculated from the radial pulses by Fourier analysis and transfer functions. These calculated aortic pulses were compared with directly recorded aortic pulses by a transducer-tip catheter in a series of 50 patients undergoing cardiac catheterization. The correlation coefficient (r) of the measured versus the calculated aortic systolic blood pressure was ϩ0.89, but the scatter was large (standard deviation of the differencesϭϮ11.3 mm Hg). The pulse pressure correlations were less good (rϭϩ0.79) and also had a large scatter (Ϯ13.6 mm Hg). The average calculated pulse pressure was 11.5 mm Hg lower than the measured value because the cuff diastolic blood pressures, used to calibrate the radial pulses, were systematically higher than those in the aorta (8.9 mm Hg). Multivariable analysis incorporating height, age, heart rate, and ejection fraction as additional, independent variables eliminated mean differences between the new "predicted" and measured pressures, significantly improved correlation coefficients, and reduced the scatter. However, the improvements were small. The inaccuracy of the oscillometric cuff method for measuring arm blood pressure appears to be the limiting factor in the prediction of clinically useful, noninvasive aortic pressures. Key Words: aorta Ⅲ arterial pressure Ⅲ Fourier analysis Ⅲ blood pressure determination T he cuff technique for the measurement of brachial-artery (BA) pressure has been of inestimable benefit in the diagnosis and treatment of multiple diseases. It is well known, however, that BA pressure is not the same as and is often an inaccurate estimate of central aortic pressure. The difference between the 2 pressures is difficult to predict because it is influenced by many factors, such as body height, age, heart rate, stroke volume, ejection time, and the distensibility of the conduit arterial tree. An accurate, noninvasive method to measure aortic pressures would be an important clinical advance. It would permit better estimates of cardiac work, better diagnoses of hypertension, and the response to antihypertensive treatment; improve the correction of hemodynamic abnormalities in hypotensive states; and offer better assessments of the pressor responses to exercise stress, during which arm pressures are known to be falsely elevated. 1 Aortic pressures can now only be measured accurately by invasive catheterization, a method unsuitable for widespread clinical use. O'Rourke and colleagues 2-5 have proposed a solution involving transformation of the applanated and calibrated radial-art...

show abstract

“…Tube diameter and diameter fluctuation over time were measured with a specially designed ultrasonic echotracking device (NIUS, Asulab) with a precision of 3 m. 18 Pressure was measured using pressure catheters (Millar Instruments) inserted at the level of each tube. Shear stress was computed from flow rate and diameter measurements using a Womersley approximation.…”

Section: Experimental Systemmentioning

confidence: 99%

Influence of Oscillatory and Unidirectional Flow Environments on the Expression of Endothelin and Nitric Oxide Synthase in Cultured Endothelial Cells

Ziegler

Bouzourène

Harrison

et al. 1998

ATVB

294

213

View full text Add to dashboard Cite

Abstract-In vivo, endothelial cells (ECs) are subjected to a complex mechanical environment composed of shear stress, pressure, and circumferential stretch. The aim of this study was to subject bovine aortic ECs to a pulsatile pressure oscillating from 70 to 130 mm Hg (mean of 100 mm Hg) in combination with pulsatile shear stresses from 0.1 to 6 dyne/cm 2 (1 dyne/cm 2 ϭ0.1 N/m 2 ) with or without a cyclic circumferential stretch of 4% for 1, 4, and 24 hours. The effect of highly reversing oscillatory shear stress (range Ϫ3 to ϩ3 dyne/cm 2 , mean of 0.3 dyne/cm 2 ) typical of regions prone to the development of atherosclerotic plaques was also studied at 4 and 24 hours. Endothelin-1 (ET-1) and endothelial constitutive nitric oxide synthase (ecNOS) mRNA expression was time and mechanical force dependent. ET-1 mRNA was maximal at 4 hours and decreased to less than static culture expression at 24 hours, whereas ecNOS mRNA increased over time. Pressure combined with low shear stress upregulated ET-1 and ecNOS mRNA compared with static control. Additional increase in expression for both genes was observed under a combination of higher shear stress and pressure. A cyclic circumferential stretch of 4% did not induce a further increase in ET-1 and ecNOS mRNA at either low or high shear stress. Oscillatory shear stress with pressure induced a higher expression of ET-1 mRNA but lower expression of ecNOS mRNA compared with unidirectional shear stress and pressure. We have shown that the combination of pressure and oscillatory shear stress can downregulate ecNOS levels, as well as upregulate transient expression of ET-1, compared with unidirectional shear stress. These results provide a new insight into the exact role of mechanical forces in endothelial dysfunction in regions prone to the development of atherosclerosis. (Arterioscler Thromb Vasc Biol. 1998;18:686-692.) Key Words: mechanical stress Ⅲ hemodynamics Ⅲ vascular endothelium Ⅲ nitric oxide synthase Ⅲ endothelin T he fluid mechanics of blood are known to transiently regulate vascular tone. In addition to short-term action, fluid mechanics have also been shown to regulate vascular remodeling in the case of long-term changes in pressure (hypertension) and flow rate (pregnancy, arteriovenous shunts, and exercise).1 More importantly, it has been demonstrated that the localization of the atherosclerotic plaque is correlated with regions characterized by oscillatory shear stress environment. 2 This regulation has been demonstrated in part to occur via two molecules secreted by the ECs and which have been identified as ET-1 and NO.ET-1 is a 21-amino acid peptide acting as a powerful vasoconstrictor and an SMC mitogen.3 ET-1 is thought to play an active role in SMC proliferation during remodeling of arteries. ET-1 mRNA expression has been shown to be transiently stimulated at 1 to 4 hours in cultured porcine aortic ECs exposed to a shear stress of 5 dyne/cm 2 (1 dyne/cm 2 ϭ0.1 N/m 2 ) and 30 minutes in BAECs exposed to 15 dyne/cm 2 . 4,5 Longer time exposure to 15 dyne/cm 2...

show abstract

Spontaneous diameter oscillations of the radial artery in humans

Cited by 47 publications

References 0 publications

Validation of Circumferential Carotid Artery Strain as a Screening Tool for Subclinical Atherosclerosis

Validation of Circumferential Carotid Artery Strain as a Screening Tool for Subclinical Atherosclerosis

Clinical Utility of Aortic Pulses and Pressures Calculated From Applanated Radial-Artery Pulses

Influence of Oscillatory and Unidirectional Flow Environments on the Expression of Endothelin and Nitric Oxide Synthase in Cultured Endothelial Cells

Contact Info

Product

Resources

About