Effective Arterial Elastance Is Insensitive to Pulsatile Arterial Load

Effective arterial elastance (EA) was proposed as a lumped parameter that incorporates pulsatile and resistive afterload and is increasingly being used in clinical studies. Theoretical modeling studies suggest that EA is minimally affected by pulsatile load, but little human data are available. We assessed the relationship between EA and arterial load determined noninvasively from central pressure–flow analyses among middle-aged adults in the general population (n=2367) and a diverse clinical population of older adults (n=193). In a separate study, we investigated the sensitivity of EA to changes in pulsatile load induced by isometric exercise (n=73). The combination of systemic vascular resistance and heart rate predicted 95.6% and 97.8% of the variability in EA among middle-aged and older adults, respectively. EA demonstrated a quasi-perfect linear relationship with the ratio of systemic vascular resistance/heart period (middle-aged adults, R=0.972; older adults, R=0.99; P<0.0001). Aortic characteristic impedance, total arterial compliance, reflection magnitude, and timing accounted together for <1% of the variability in EA in either middle-aged or older adults. Despite pronounced changes in pulsatile load induced by isometric exercise, changes in EA were not independently associated with changes pulsatile load but were rather a nearly perfect linear function of the ratio of systemic vascular resistance/heart period (R=0.99; P<0.0001). Our findings demonstrate that EA is simply a function of systemic vascular resistance and heart rate and is negligibly influenced by (and insensitive to) changes in pulsatile afterload in humans. Its current interpretation as a lumped parameter of pulsatile and resistive afterload should thus be reassessed.

[1]  L. Wurfel.  Mcdonald S Blood Flow In Arteries Theoretical Experimental And Clinical Principles , 2016 .

[2]  Michael A. Burke,et al.  Prognostic Importance of Pathophysiologic Markers in Patients With Heart Failure and Preserved Ejection Fraction , 2014, Circulation. Heart failure.

[3]  M. O'Rourke,et al.  Pulsatile hemodynamics in patients with exertional dyspnea: potentially of value in the diagnostic evaluation of suspected heart failure with preserved ejection fraction. , 2013, Journal of the American College of Cardiology.

[4]  P. Segers,et al.  Early and Late Systolic Wall Stress Differentially Relate to Myocardial Contraction and Relaxation in Middle-Aged Adults: The Asklepios Study , 2013, Hypertension.

[5]  I. Kullo,et al.  Sex differences in arterial stiffness and ventricular-arterial interactions. , 2013, Journal of the American College of Cardiology.

[6]  R. Kronmal,et al.  Arterial wave reflections and incident cardiovascular events and heart failure: MESA (Multiethnic Study of Atherosclerosis). , 2012, Journal of the American College of Cardiology.

[7]  P. Segers,et al.  Arterial Properties as Determinants of Time-Varying Myocardial Stress in Humans , 2012, Hypertension.

[8]  P. Segers,et al.  Noninvasive evaluation of left ventricular afterload: part 2: arterial pressure-flow and pressure-volume relations in humans. , 2010, Hypertension.

[9]  P. Segers,et al.  Noninvasive evaluation of left ventricular afterload: part 1: pressure and flow measurements and basic principles of wave conduction and reflection. , 2010, Hypertension.

[10]  N. Ohte,et al.  Impact of arterial load on left ventricular diastolic function in patients undergoing cardiac catheterization for coronary artery disease. , 2010, Circulation journal : official journal of the Japanese Circulation Society.

[11]  Patrick Segers,et al.  Arterial pulsatile hemodynamic load induced by isometric exercise strongly predicts left ventricular mass in hypertension. , 2010, American journal of physiology. Heart and circulatory physiology.

[12]  Einar Heiberg,et al.  Design and validation of Segment - freely available software for cardiovascular image analysis , 2010, BMC Medical Imaging.

[13]  Akshay S. Desai,et al.  Central aortic stiffness is increased in patients with heart failure and preserved ejection fraction. , 2009, Journal of cardiac failure.

[14]  P. Segers,et al.  Arterial Load and Ventricular-Arterial Coupling: Physiologic Relations With Body Size and Effect of Obesity , 2009, Hypertension.

[15]  M. Keane,et al.  Time-Varying Myocardial Stress and Systolic Pressure-Stress Relationship: Role in Myocardial-Arterial Coupling in Hypertension , 2009, Circulation.

[16]  Gary F. Mitchell,et al.  Clinical achievements of impedance analysis , 2009, Medical & Biological Engineering & Computing.

[17]  M. O'Rourke,et al.  Arterial stiffness and arterial wave reflections are associated with systolic and diastolic function in patients with normal ejection fraction. , 2008, American journal of hypertension.

[18]  B. Westerhof,et al.  Different role of wave reflection magnitude and timing on left ventricular mass reduction during antihypertensive treatment , 2008, Journal of hypertension.

[19]  W. Nichols,et al.  Effects of Arterial Stiffness, Pulse Wave Velocity, and Wave Reflections on the Central Aortic Pressure Waveform , 2008, Journal of clinical hypertension.

[20]  A. Biolo,et al.  Arterial stiffness and vascular load in heart failure. , 2008, Congestive heart failure.

[21]  D. Kass,et al.  Impact of arterial load and loading sequence on left ventricular tissue velocities in humans. , 2007, Journal of the American College of Cardiology.

[22]  Patrick Segers,et al.  Assessment of pressure wave reflection: getting the timing right! , 2007, Physiological measurement.

[23]  G. De Backer,et al.  Noninvasive (Input) Impedance, Pulse Wave Velocity, and Wave Reflection in Healthy Middle-Aged Men and Women , 2007, Hypertension.

[24]  Jean-Claude Tardif,et al.  Long-Term Trandolapril Treatment Is Associated With Reduced Aortic Stiffness: The Prevention of Events With Angiotensin-Converting Enzyme Inhibition Hemodynamic Substudy , 2007, Hypertension.

[25]  Pascal Verdonck,et al.  Rationale, design, methods and baseline characteristics of the Asklepios Study , 2007, European journal of cardiovascular prevention and rehabilitation : official journal of the European Society of Cardiology, Working Groups on Epidemiology & Prevention and Cardiac Rehabilitation and Exercise Physiology.

[26]  J. Izzo,et al.  Changes in Aortic Stiffness and Augmentation Index After Acute Converting Enzyme or Vasopeptidase Inhibition , 2005, Hypertension.

[27]  T. Yamanaka,et al.  Nitroglycerin Improves Left Ventricular Relaxation by Changing Systolic Loading Sequence in Patients with Excessive Arterial Load , 2005, Journal of cardiovascular pharmacology.

[28]  Marc A Pfeffer,et al.  Determinants of Elevated Pulse Pressure in Middle-Aged and Older Subjects With Uncomplicated Systolic Hypertension: The Role of Proximal Aortic Diameter and the Aortic Pressure-Flow Relationship , 2003, Circulation.

[29]  Yves Lecarpentier,et al.  Contribution of systemic vascular resistance and total arterial compliance to effective arterial elastance in humans. , 2003, American journal of physiology. Heart and circulatory physiology.

[30]  Patrick Segers,et al.  Relation of effective arterial elastance to arterial system properties. , 2002, American journal of physiology. Heart and circulatory physiology.

[31]  C H Chen,et al.  Noninvasive single-beat determination of left ventricular end-systolic elastance in humans. , 2001, Journal of the American College of Cardiology.

[32]  M. Pfeffer,et al.  Pulsatile Hemodynamics in Congestive Heart Failure , 2001, Hypertension.

[33]  M. Yano,et al.  Influence of aortic impedance on the development of pressure-overload left ventricular hypertrophy in rats. , 1996, Circulation.

[34]  S. Sasayama,et al.  Change in aortic end-systolic pressure by alterations in loading sequence and its relation to left ventricular isovolumic relaxation. , 1996, Circulation.

[35]  N Westerhof,et al.  Haemodynamic basis for the development of left ventricular failure in systolic hypertension and for its logical therapy. , 1995, Journal of hypertension.

[36]  N Westerhof,et al.  Evaluation of methods for estimation of total arterial compliance. , 1995, The American journal of physiology.

[37]  David A. Kass,et al.  Effective Arterial Elastance as Index of Arterial Vascular Load in Humans , 1992, Circulation.

[38]  W. Lew,et al.  Influence of systolic pressure profile on rate of left ventricular pressure fall. , 1991, The American journal of physiology.

[39]  K P Brin,et al.  Estimation of total arterial compliance: an improved method and evaluation of current methods. , 1986, The American journal of physiology.

[40]  K. Sagawa,et al.  Optimal Arterial Resistance for the Maximal Stroke Work Studied in Isolated Canine Left Ventricle , 1985, Circulation research.

[41]  M. Hori,et al.  Altered loading sequence as an underlying mechanism of afterload dependency of ventricular relaxation in hearts in situ. , 1985, Japanese circulation journal.

[42]  W L Maughan,et al.  Left ventricular interaction with arterial load studied in isolated canine ventricle. , 1983, The American journal of physiology.

[43]  M F O'Rourke,et al.  Vascular impedance in studies of arterial and cardiac function. , 1982, Physiological reviews.

[44]  N. Westerhof,et al.  Aortic Input Impedance in Normal Man: Relationship to Pressure Wave Forms , 1980, Circulation.

[45]  W. Milnor,et al.  Arterial impedance as ventricular afterload. , 1975, Circulation research.

[46]  N. Westerhof,et al.  Forward and backward waves in the arterial system. , 1972, Cardiovascular research.