Mechanical characterization of a model of a multicomponent cardiac fibre

We have developed a model of a cardiac fibre composed of several contractile units in series and activated in succession; each unit behaves according to Wong's model. The main difference between the multicomponent model and the classic monocomponent model is that it is possible to take into account both the dynamic phenomena due to the propagation of the activation signal along the fibre and the contractility of each unit from which the fibre is constructed. Isometric and isotonic contractions have been simulated under different conditions in terms of preload, afterload, frequency and number of inhibited units. The analysis of the results allows us to assert that the multicomponent fibre behaviour is in good agreement with experimental results from the literature. We believe that the multicomponent cardiac fibre should be regarded as a powerful tool linking the sarcomere contraction with that of the whole ventricle.