Traditional muscle physiology undergoes radical changes in the setting of continuously electrostimulated skeletal muscle utilization for biomechanical circulatory assist. Healthy ''transformed'' working skeletal muscle never loses the characteristics germane to striated muscle fibers. It only undergoes a multiplicity of changes which are always dynamic in nature. Thermodynamic parameters applied to the study of biologic phenomena have long provided a unique approach for analyzing the physiology of the skeletal muscle cells. The laws of thermodynamics, with their concepts of negentropy, entropy, and enthalpy, traditionally are applied to the non-living world. However, after forty years of fundamental ground work by Archibald Vivian Hill, other scientists have made it possible to utilize these concepts to study the performance of complex living systems. This essay aims to shed some light and to add a new perspective to the use of striated muscle so it may perform myocardial-like work efficiently for prolonged periods of time. Understanding the basic principles of thermodynamics and applying the concept to designing both stimulators and customized individual programs, may prove beneficial to a number of patients now undergoing cardiomyoplasty, and in the future to others destined to receive muscle assisted cardiocirculatory augmentation procedures now in the experimental stage.
