Descriptive ability of three local left ventricle pump models

Three viscoelastic models of the left-ventricular (LV) pumping function are proposed and compared with the classical elastance-resistance description starting from data measured on dogs: isovolumic pressure at a given preload together with a series of LV pressure and outflow curves with graded aortic occlusions. The comparison criterion takes into account descriptive ability, robustness of the estimates, and their physical interpretation. The analysis confirms the presence of both activation and deactivation phenomena. The dependence of stiffness and resistance on afterload agrees with known myocardial features and supports the local validity of the proposed models.<>