The present invention provides device and methods for assisting in the ventricular function of a treated heart, and tools for delivering and attaching elements of said devices to the wall of the heart. In general the devices of the invention are designed to assist in the ventricular function of the heart by utilizing elastic and/or magnetic, elements designed to apply radially and/or tangentially directed forces over the wall of the heart, and/or alter the pressure conditions inside ventricule(s) of the heart. Embodiments of the invention may utilize restrictive elements which may optionally be attached over the heart during the implantation procedure, or at a later time, by changing the mode of operation of an implanted device of the invention .