Myocardium from the Left and Right Ventricles of Human Hearts have Similar Mechanical Properties

Abstract

The left and right ventricles (LV and RV) of human hearts generate different pressures. It is not clear if this difference in pressure reflects the arrangement of cells in each ventricle, or the force generating capacity of individual myocytes. Thus, the aim of this study is to test the hypothesis that cells from the RV and LV of human hearts have different mechanical properties. Chemically permeabilized multicellular preparations from both ventricles of hearts explanted from patients with heart failure (n=12) and patients without a history of heart failure (non-failing samples) (n=6) were attached between a force transducer and a motor to determine mechanical properties. Similar to prior data from our laboratory, heart failure reduced isometric force and maximum power by ∼40% (p 0.05). There were no significant interactions between heart failure status and region. These data imply that myocardium from the left and right ventricles has comparable mechanical properties and that heart failure impacts both ventricles in a similar way. Interventricular differences in chamber function are most likely to reflect structural effects as opposed to the intrinsic contractile properties of the cells.