Abstract: The present invention is directed to a contractible and expandable jacket configured to encase at least a portion of a patient's heart. The jacket has a plurality of individual contractile cells with each of the cells having a first electrically conductive coil and a second electrically conductive coil spaced from the first coil. The first coil preferably defines at least in part a first periphery of an inner nucleus of the cell and the second coil preferably defining at least in part an outer portion of the cell spaced outwardly from the inner nucleus. When electrical current passes through the first and second coils in opposite directions, the cell contracts and when electrical current passes through the first and second coils in the same direction the cell expands. Each of the individual cells has conductive appendages for conducting information to and from the individual cells.