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Efficiency of cardiac muscle: thermodynamic and statistical mechanical considerations
1Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland.
Abstract:
The efficiency of cardiac muscle can be easily defined using thermodynamics and statistical mechanics. While thermodynamic definitions allow absolute measures of efficiency in terms of work output and free energy input, they do not provide insights into the underlying contraction mechanisms. The construction of molecular kinetics models of muscle, such as the cross-bridge theory, in conjunction with the use of statistical mechanics provides a framework for the examination of efficiency. The expressions of efficiency derived in this manner will be thermodynamically consistent and can be compared to experimental measurements, thereby rendering insight into cardiac energetics.
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