Abstract
In search for a ventricular index of left ventricular contractility which should be independent of preload and afterload as much as possible (see also Chapter III), Suga and Sugawa in 1974 [1] developed the Emax concept (end-systolic pressure-volume ratio) which was based on the time-varying elastance theory of ventricular contraction. This theory can be best described by a spring as demonstrated in Figure 1: at end-diastole (Figure 1A), the thin spring symbolizes the compliant chamber wall, i.e., elastance is low. At end-systole, the thick spring symbolizes the stiffened chamber wall, i.e., elastance has increased and has become maximum (Figure 1B).
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References
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© 2002 Springer Science+Business Media New York
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Holubarsch, C.J.F. (2002). The EMAX and the PVA Concept. In: Mechanics and Energetics of the Myocardium. Basic Science for the Cardiologist, vol 10. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-0879-3_9
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DOI: https://doi.org/10.1007/978-1-4615-0879-3_9
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