the present invention relates to therapeutic devices to work in conjunction with a diseased or failing heart to satisfy the hemodynamic needs of a patient . more particularly , the invention relates to a fully implantable device for assisting a heart to pump blood by intermittently applying pressure to at least a portion of the ventricular surface of the heart , preferably both the atrial and ventricular surfaces , at predetermined or possibly pre - programmed intervals to assist the heart to provide adequate hemodynamic output by sensing demand of the human body . in short , the present invention assists the maintenance of , or reestablishes , the normal contraction sequence of a healthy heart .