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Cardiac Work, Energy and Power

  • Nicolaas Westerhof
  • Nikolaos Stergiopulos
  • Mark I. M. Noble
  • Berend E. Westerhof
Chapter

Abstract

External work per beat, stroke work, can be determined from the area contained in the pressure-volume loop (Joule). Multiplication of stroke work by Heart Rate gives cardiac power (J/s or Watt; work per unit time). External power also can be calculated from the instantaneous product of ventricular (or aortic) pressure and flow. The calculation of energy and power does not require a linear system, as, for example, in the calculation of resistance and impedance. This makes the use of energy and power very broadly applicable in hemodynamics. Power and work are a characterization of heart and load together, while the End-Systolic Pressure-Volume Relation and Pump Function Graph characterize the heart.

Keywords

Stroke work Energy External power Pump function Pressure-volume relation 

References

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Copyright information

© Springer International Publishing AG, part of Springer Nature 2019

Authors and Affiliations

  • Nicolaas Westerhof
    • 1
  • Nikolaos Stergiopulos
    • 2
  • Mark I. M. Noble
    • 3
  • Berend E. Westerhof
    • 1
  1. 1.Department of Pulmonary Diseases, Amsterdam Cardiovascular SciencesVU University Medical CenterAmsterdamThe Netherlands
  2. 2.Laboratory of Hemodynamics and Cardiovascular TechnologyEcole Polytechnique Fédérale de Lausanne (EPFL), Institute of BioengineeringLausanneSwitzerland
  3. 3.Cardiovascular Medicine, Department of Medicine and TherapeuticsUniversity of AberdeenAberdeenUnited Kingdom

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