Abstract: Cardiac ventricular assist apparatus adapted to be placed by insertion through an incision in the wall of the upper abdomen below the rib cage and an incision in the inferior aspect of the pericardium proximate the heart apex comprises a flexible bladder assembly that adapted to be passed through the incision in the pericardium to a position between the pericardial sac and the epicardium. The bladder assembly is of a size such and shape such as to be engageable with a substantial portion of the outer surface of the left ventricle of a heart. The bladder assembly includes a distensible pumping bladder that is attached to a tube through which a gas can be introduced into it to compress the left ventricle and withdrawn from it to allow the ventricle to fill and a non-distensible retaining bladder, which is substantially coextensive with the pumping bladder and receives a packed body of particulate material.