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Figure 1. Pressure-volume diagrams in thermodynamics (steam engine) and in cardiovascular physiology. (A) A pressure-volume diagram is used in thermodynamics to describe a thermal cycle involving changes in volume and pressure in a system. (B) The cardiac cycle can be analyzed as a thermodynamic cycle. 1: expansion (work out); 2: heat in (combustion); 3: compression (work in); 4: heat out (exhaust); a: isovolumic contraction; b: ejection phase; c: isovolumic relaxation; d: filling. m: Mass; P: Pressure; SV: Stroke volume; SW: Stroke work; v: Velocity.
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Figure 2. The 'Dorian Gray effect'. (A) Cardiac work is an orderly energy transfer that organizes the body's molecules to do work. The heart's ability to offset the increasing tissues'entropic burden by the energy flow can be threatened by the increase of tissues'randomness and disorder as a result of various disease states; the heart may become a vulnerable target of a number of attacks either from the internal environment (metabolic) or from the external environment.
(B) This effect is known as the 'Dorian Gray effect'of the heart.
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Figure 3. Negative entropy. The ability of flushing out the excess of entropy is one of the most outstanding features of cellular life. The function of the heart is to organize body's the molecules to do work and this energy flow helps to offset the increasing body's entropic trend primarily through the external work made by the skeletal muscles. With the aid of application of the general system theory, the heart could be viewed as a connection between surroundings (biosphere) and the metabolism of the body.
(Figure omitted. See article PDF.)
Thermodynamics is a branch of physics that deals with energy and work of a system. The term thermodynamics was originally applied to the science dealing with the motive power of heat, or the transformation of heat into mechanical work or vice versa . Thereafter, the subject was extended to the more generalized concept of energy transformation. While this subject is of very great importance to physicists and engineers, it is rather unfamiliar in the field of cardiovascular medicine. Like all pumps, the heart requires a source of energy and oxygen in order to function, that is, transferred from the hydrolysis of ATP;...