Mechanical properties of the stimulated papillary muscle in quick-release experiments

The behavior of heart muscle in the stimulated state is a subject of much controversy. A brief summary of the conclusions drawn by some investigators is given to bring the conflicts to focus. In 1970 Fung formulated the general problem incorporating Hill's three-elements model and Huxley's sliding element theory. This formalism is of general validity and is adopted here to study the papillary muscle behavior. Preliminary results obtained using quick-release technique are presented.