title: Effective arterial elastance is insensitive to pulsatile arterial load.
abstract: Effective arterial elastance (E(A)) 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 E(A) is minimally affected by pulsatile load, but little human data are available. We assessed the relationship between E(A) 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 E(A) 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 E(A) among middle-aged and older adults, respectively. E(A) 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 E(A) in either middle-aged or older adults. Despite pronounced changes in pulsatile load induced by isometric exercise, changes in E(A) 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 E(A) 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.
authors: From the Department of Medicine, Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C., P.Z.); Department of Medicine, Philadelphia VA Medical Center, PA (J.A.C., P.S.-K., S.R.A., S.G.); Department of Cardiovascular Diseases, Ghent University Hospital, Ghent, Belgium (E.R.R., M.L.D.B., D.D.B.); and Department of Public Health (E.R.R.), Department of Industrial Technology and Construction (T.C.), and Institute Biomedical Technology, iMinds Future Health Department (T.C., P.S.), Ghent University, Ghent, Belgium. Julio.chirinos@uphs.upenn.edu.
authors: Julio A
authors: JA
authors: Chirinos
authors: From the Department of Medicine, Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C., P.Z.); Department of Medicine, Philadelphia VA Medical Center, PA (J.A.C., P.S.-K., S.R.A., S.G.); Department of Cardiovascular Diseases, Ghent University Hospital, Ghent, Belgium (E.R.R., M.L.D.B., D.D.B.); and Department of Public Health (E.R.R.), Department of Industrial Technology and Construction (T.C.), and Institute Biomedical Technology, iMinds Future Health Department (T.C., P.S.), Ghent University, Ghent, Belgium.
authors: Ernst R
authors: ER
authors: Rietzschel
authors: From the Department of Medicine, Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C., P.Z.); Department of Medicine, Philadelphia VA Medical Center, PA (J.A.C., P.S.-K., S.R.A., S.G.); Department of Cardiovascular Diseases, Ghent University Hospital, Ghent, Belgium (E.R.R., M.L.D.B., D.D.B.); and Department of Public Health (E.R.R.), Department of Industrial Technology and Construction (T.C.), and Institute Biomedical Technology, iMinds Future Health Department (T.C., P.S.), Ghent University, Ghent, Belgium.
authors: Prithvi
authors: P
authors: Shiva-Kumar
authors: From the Department of Medicine, Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C., P.Z.); Department of Medicine, Philadelphia VA Medical Center, PA (J.A.C., P.S.-K., S.R.A., S.G.); Department of Cardiovascular Diseases, Ghent University Hospital, Ghent, Belgium (E.R.R., M.L.D.B., D.D.B.); and Department of Public Health (E.R.R.), Department of Industrial Technology and Construction (T.C.), and Institute Biomedical Technology, iMinds Future Health Department (T.C., P.S.), Ghent University, Ghent, Belgium.
authors: Marc L
authors: ML
authors: De Buyzere
authors: From the Department of Medicine, Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C., P.Z.); Department of Medicine, Philadelphia VA Medical Center, PA (J.A.C., P.S.-K., S.R.A., S.G.); Department of Cardiovascular Diseases, Ghent University Hospital, Ghent, Belgium (E.R.R., M.L.D.B., D.D.B.); and Department of Public Health (E.R.R.), Department of Industrial Technology and Construction (T.C.), and Institute Biomedical Technology, iMinds Future Health Department (T.C., P.S.), Ghent University, Ghent, Belgium.
authors: Payman
authors: P
authors: Zamani
authors: From the Department of Medicine, Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C., P.Z.); Department of Medicine, Philadelphia VA Medical Center, PA (J.A.C., P.S.-K., S.R.A., S.G.); Department of Cardiovascular Diseases, Ghent University Hospital, Ghent, Belgium (E.R.R., M.L.D.B., D.D.B.); and Department of Public Health (E.R.R.), Department of Industrial Technology and Construction (T.C.), and Institute Biomedical Technology, iMinds Future Health Department (T.C., P.S.), Ghent University, Ghent, Belgium.
authors: Tom
authors: T
authors: Claessens
authors: From the Department of Medicine, Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C., P.Z.); Department of Medicine, Philadelphia VA Medical Center, PA (J.A.C., P.S.-K., S.R.A., S.G.); Department of Cardiovascular Diseases, Ghent University Hospital, Ghent, Belgium (E.R.R., M.L.D.B., D.D.B.); and Department of Public Health (E.R.R.), Department of Industrial Technology and Construction (T.C.), and Institute Biomedical Technology, iMinds Future Health Department (T.C., P.S.), Ghent University, Ghent, Belgium.
authors: Salvatore
authors: S
authors: Geraci
authors: From the Department of Medicine, Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C., P.Z.); Department of Medicine, Philadelphia VA Medical Center, PA (J.A.C., P.S.-K., S.R.A., S.G.); Department of Cardiovascular Diseases, Ghent University Hospital, Ghent, Belgium (E.R.R., M.L.D.B., D.D.B.); and Department of Public Health (E.R.R.), Department of Industrial Technology and Construction (T.C.), and Institute Biomedical Technology, iMinds Future Health Department (T.C., P.S.), Ghent University, Ghent, Belgium.
authors: Prasad
authors: P
authors: Konda
authors: From the Department of Medicine, Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C., P.Z.); Department of Medicine, Philadelphia VA Medical Center, PA (J.A.C., P.S.-K., S.R.A., S.G.); Department of Cardiovascular Diseases, Ghent University Hospital, Ghent, Belgium (E.R.R., M.L.D.B., D.D.B.); and Department of Public Health (E.R.R.), Department of Industrial Technology and Construction (T.C.), and Institute Biomedical Technology, iMinds Future Health Department (T.C., P.S.), Ghent University, Ghent, Belgium.
authors: Dirk
authors: D
authors: De Bacquer
authors: From the Department of Medicine, Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C., P.Z.); Department of Medicine, Philadelphia VA Medical Center, PA (J.A.C., P.S.-K., S.R.A., S.G.); Department of Cardiovascular Diseases, Ghent University Hospital, Ghent, Belgium (E.R.R., M.L.D.B., D.D.B.); and Department of Public Health (E.R.R.), Department of Industrial Technology and Construction (T.C.), and Institute Biomedical Technology, iMinds Future Health Department (T.C., P.S.), Ghent University, Ghent, Belgium.
authors: Scott R
authors: SR
authors: Akers
authors: From the Department of Medicine, Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C., P.Z.); Department of Medicine, Philadelphia VA Medical Center, PA (J.A.C., P.S.-K., S.R.A., S.G.); Department of Cardiovascular Diseases, Ghent University Hospital, Ghent, Belgium (E.R.R., M.L.D.B., D.D.B.); and Department of Public Health (E.R.R.), Department of Industrial Technology and Construction (T.C.), and Institute Biomedical Technology, iMinds Future Health Department (T.C., P.S.), Ghent University, Ghent, Belgium.
authors: Thierry C
authors: TC
authors: Gillebert
authors: From the Department of Medicine, Perelman School of Medicine and Hospital of the University of Pennsylvania, Philadelphia (J.A.C., P.Z.); Department of Medicine, Philadelphia VA Medical Center, PA (J.A.C., P.S.-K., S.R.A., S.G.); Department of Cardiovascular Diseases, Ghent University Hospital, Ghent, Belgium (E.R.R., M.L.D.B., D.D.B.); and Department of Public Health (E.R.R.), Department of Industrial Technology and Construction (T.C.), and Institute Biomedical Technology, iMinds Future Health Department (T.C., P.S.), Ghent University, Ghent, Belgium.
authors: Patrick
authors: P
authors: Segers
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D001158:Arteries / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D002318:Cardiovascular Diseases / Q000503:physiopathology*; D004548:Elasticity / Q000502:physiology*; D015444:Exercise / Q000502:physiology; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008365:Manometry; D008875:Middle Aged; D011673:Pulsatile Flow / Q000502:physiology*; D014655:Vascular Resistance / Q000502:physiology; D059289:Vascular Stiffness / Q000502:physiology*
keywords: arterial load; characteristic impedance; effective arterial elastance; total arterial compliance; ventricular–arterial coupling; wave reflections