Published Online
on April 2, 2007

A more recent version of this article appeared on June 1, 2007

This Article Full Text (PDF) Data Supplement All Versions of this Article: 49/6/1248    most recent HYPERTENSIONAHA.106.085480v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Segers, P. Search for Related Content PubMed PubMed Citation Articles by Segers, P. Related Collections Pathophysiology Other hypertension Hypertension - basic studies Other diagnostic testing Other Research Related Article

Submitted on December 2, 2006
Revised on December 24, 2006

Noninvasive (Input) Impedance, Pulse Wave Velocity, and Wave Reflection in Healthy Middle-Aged Men and Women

Patrick Segers^*; Ernst R. Rietzschel; Marc L. De Buyzere; Sebastian J. Vermeersch; Dirk De Bacquer; Luc M. Van Borte; Guy De Backer; Thierry C. Gillebert; Pascal R. Verdonck; on behalf of the Asklepios investigators

From the Cardiovascular Mechanics and Biofluid Dynamics (P.S., S.J.V., P.R.V.), IBiTech, Ghent University, Ghent, Belgium; and the Departments of Cardiovascular Diseases (E.R.R., M.L.D.B., T.C.G.), Public Health (D.D.B., G.D.B.), and Pharmacology (L.M.V.B.), Ghent University Hospital, Ghent, Belgium.

^* To whom correspondence should be addressed. E-mail: patrick.segers{at}ugent.be.

Abstract--The relation between arterial function indices, such as pulse wave velocity and augmentation index with parameters derived from input impedance analysis, is still incompletely understood. Carotid pressure, central flow waveforms, and pulse wave velocity were noninvasively acquired in 2026 apparently healthy, middle-aged subjects (1052 women and 974 men) 35 to 55 years old at inclusion. Input and characteristic impedance, reflection coefficient, the ratio of backward-to-forward pressure amplitude (reflection magnitude), and augmentation index were derived. Pulse wave velocity increased by 15% (from 6.1 to 7.0 m/s) both in men and women. In qualitative terms, input impedance evolved from a pattern indicative of wave transmission and reflection to a pattern more compatible with a windkessel-like system. In women, a decrease in total arterial compliance led to an increased input impedance in the low frequency range, whereas few changes were observed in men. Characteristic impedance did not change with age in women and even decreased in men (P<0.001) and could not be identified as the primary determinant of central pulse pressure. Augmentation index increased with age, as was expected, and was systematically higher in women (P<0.001). Reflection coefficient and reflection magnitude increased with age (P<0.001) without gender differences. We conclude that, in healthy middle-aged subjects, the age-related increase in arterial stiffness (pulse wave velocity) is not fully paralleled by an increase in arterial impedance, suggesting a role for age-dependent modulation of aortic cross-sectional area. Wave reflection increases with age and is not higher in women than in men.

Key words: cardiovascular physiology • blood pressure • vascular capacitance • arteries • biomechanics

Related Article:

Impedance Progress: Aortic Diameter Rears Its Head Again?

Gary F. Mitchell
Hypertension 2007 49: 1207-1209. [Extract] [Full Text] [PDF]

This article has been cited by other articles:

				A. J. Baksi, T. A. Treibel, J. E. Davies, N. Hadjiloizou, R. A. Foale, K. H. Parker, D. P. Francis, J. Mayet, and A. D. Hughes A Meta-Analysis of the Mechanism of Blood Pressure Change With Aging. J. Am. Coll. Cardiol., November 24, 2009; 54(22): 2087 - 2092. [Abstract] [Full Text] [PDF]

				J. A. Chirinos, E. R. Rietzschel, M. L. De Buyzere, D. De Bacquer, T. C. Gillebert, A. K. Gupta, P. Segers, and on behalf of the Asklepios investigators Arterial Load and Ventricular-Arterial Coupling: Physiologic Relations With Body Size and Effect of Obesity Hypertension, September 1, 2009; 54(3): 558 - 566. [Abstract] [Full Text] [PDF]

				M. Cecelja, B. Jiang, K. McNeill, B. Kato, J. Ritter, T. Spector, and P. Chowienczyk Increased wave reflection rather than central arterial stiffness is the main determinant of raised pulse pressure in women and relates to mismatch in arterial dimensions: a twin study. J. Am. Coll. Cardiol., August 18, 2009; 54(8): 695 - 703. [Abstract] [Full Text] [PDF]

				M. F. O'Rourke and C. S. Hayward The pulse of cardiology: quo vadis? J. Am. Coll. Cardiol., August 18, 2009; 54(8): 714 - 717. [Full Text] [PDF]

				P. Segers, D. Mahieu, J. Kips, E. Rietzschel, M. De Buyzere, D. De Bacquer, S. Bekaert, G. De Backer, T. Gillebert, P. Verdonck, et al. Amplification of the Pressure Pulse in the Upper Limb in Healthy, Middle-Aged Men and Women Hypertension, August 1, 2009; 54(2): 414 - 420. [Abstract] [Full Text] [PDF]

				J. A. Chirinos, P. Segers, A. K. Gupta, A. Swillens, E. R. Rietzschel, M. L. De Buyzere, J. N. Kirkpatrick, T. C. Gillebert, Y. Wang, M. G. Keane, et al. Time-Varying Myocardial Stress and Systolic Pressure-Stress Relationship: Role in Myocardial-Arterial Coupling in Hypertension Circulation, June 2, 2009; 119(21): 2798 - 2807. [Abstract] [Full Text] [PDF]

				J. G. Kips, E. R. Rietzschel, M. L. De Buyzere, B. E. Westerhof, T. C. Gillebert, L. M. Van Bortel, and P. Segers Evaluation of Noninvasive Methods to Assess Wave Reflection and Pulse Transit Time From the Pressure Waveform Alone Hypertension, February 1, 2009; 53(2): 142 - 149. [Abstract] [Full Text] [PDF]

				J. E Davies, K. H Parker, D. P Francis, A. D Hughes, and J. Mayet What is the role of the aorta in directing coronary blood flow? Heart, December 1, 2008; 94(12): 1545 - 1547. [Full Text] [PDF]

				G. F. Mitchell Effects of central arterial aging on the structure and function of the peripheral vasculature: implications for end-organ damage J Appl Physiol, November 1, 2008; 105(5): 1652 - 1660. [Abstract] [Full Text] [PDF]

				E. R. Rietzschel, M. Langlois, M. L. De Buyzere, P. Segers, D. De Bacquer, S. Bekaert, L. Cooman, P. Van Oostveldt, P. Verdonck, G. G. De Backer, et al. Oxidized Low-Density Lipoprotein Cholesterol Is Associated With Decreases in Cardiac Function Independent of Vascular Alterations Hypertension, September 1, 2008; 52(3): 535 - 541. [Abstract] [Full Text] [PDF]

				S. Shibata, J. L. Hastings, A. Prasad, Q. Fu, K. Okazaki, M. D. Palmer, R. Zhang, and B. D. Levine 'Dynamic' Starling mechanism: effects of ageing and physical fitness on ventricular-arterial coupling J. Physiol., April 1, 2008; 586(7): 1951 - 1962. [Abstract] [Full Text] [PDF]

				G. F. Mitchell, V. Gudnason, L. J. Launer, T. Aspelund, and T. B. Harris Hemodynamics of Increased Pulse Pressure in Older Women in the Community-Based Age, Gene/Environment Susceptibility-Reykjavik Study Hypertension, April 1, 2008; 51(4): 1123 - 1128. [Abstract] [Full Text] [PDF]

				R. S. Vasan Pathogenesis of Elevated Peripheral Pulse Pressure: Some Reflections and Thinking Forward Hypertension, January 1, 2008; 51(1): 33 - 36. [Full Text] [PDF]

				M. F. O'Rourke, W. W. Nichols, and J. P. Murgo Noninvasive Input Impedance of the Human Systemic Circulation Hypertension, August 1, 2007; 50(2): e16 - e16. [Full Text] [PDF]

				P. Segers, E. R. Rietzschel, M. L. De Buyzere, and on behalf of the Asklepios Investigators Response to Noninvasive Input Impedance of the Human Systemic Circulation Hypertension, August 1, 2007; 50(2): e17 - e17. [Full Text] [PDF]

				G. F. Mitchell Impedance Progress: Aortic Diameter Rears Its Head Again? Hypertension, June 1, 2007; 49(6): 1207 - 1209. [Full Text] [PDF]