Pulsatile flow and pressure in human systemic arteries. Studies in man and in a multibranched model of the human systemic arterial tree.
TLDR
Pressure and flow wave contour and impedance results were interpreted with the aid of a multibranched model of the systemic arterial tree, whose parameters could be manipulated to simulate different physiological and pathological conditions.Abstract:
This study seeks to explain mechanisms responsible for the contour of pressure and flow waves and the pattern of vascular impedance in human systemic arteries. Pulsatile pressure and flow were recorded from the ascending aorta of seven patients undergoing open heart surgery and from the ascending aorta and other arteries of 17 patients at diagnostic catheterization. Ascending aortic pressure/flow relationships in the seven surgical patients were expressed as input impedance to the systemic circulation. Pressure and flow wave contour and impedance results were interpreted with the aid of a multibranched model of the systemic arterial tree, whose parameters could be manipulated to simulate different physiological and pathological conditions. Our data and data previously published on pressure and flow waves and their relationship in human subjects could be explained on the basis of two reflecting sites in the systemic circulation-one representing the resultant of all arterial terminations in the upper part of the body, and the other, some 1.5 times further away, the resultant of all arterial terminations in the lower body. The concept of the arterial system as an asymmetric T tube with two discrete ends has been advanced previously to explain the main features of pressure and flow waves and their relationship in different experimental animals. This concept appears equally applicable to human subjects. Circ Res 46: 363-372, 1980read more
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References
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Journal ArticleDOI
Analog studies of the human systemic arterial tree.
TL;DR: The performance of this electrical model is compared extensively to its real counterpart in the following areas: magnitude and phase of input impedances, wave travel along the aorta, and wave shapes of pressures and flows at different locations.
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Pressure-flow relationships and vascular impedance in man
C. J. Mills,I. T. Gabe,James H. Gault,Dean T. Mason,John Ross,Eugene Braunwald,J. P. Shillingford +6 more
TL;DR: Blood pressure and velocity waveforms were recorded in a series of patients at cardiac catheterization and the changes in shape of the waveforms are interpreted in terms of reflections and are related to computations of vascular input impedance.
Journal ArticleDOI
Input Impedance of the Systemic Circulation in Man
TL;DR: The results suggest that the subjects of group C were better able to meet the increased energy demands imposed by an abnormally high aortic input impedance, and whether the high impedances in subjects with coronary disease represent an increase with age and transmural pressure alone, or whether some additional factor is involved.
Journal ArticleDOI
Input impedance of the systemic circulation.
TL;DR: Both modulus and phase of impedance in the ascending aorta showed changes similar to those seen in other arteries when blood pressure was altered and when vasodilation occurred in the vascular bed, and so in providing a favorable impedance to pulsatile flow from the heart.
Journal ArticleDOI
Pressure Wave Transmission along the Human Aorta >CHANGES WITH AGE AND IN ARTERIAL DEGENERATIVE DISEASE
TL;DR: A decline in peripheral reflection coefficient resulting from decreased distensibility of peripheral arteries with age and in arterial degenerative disease is attributed to a decline in peripherial reflection coefficient.