An approach is disclosed for improving ventricular function of a patient's heart. In one example, an implantable apparatus includes an inflow conduit having first and second ends spaced apart from each other by a sidewall portion. An inflow valve is operatively associated with the inflow conduit to provide for substantially unidirectional flow of blood through the inflow conduit from the first end to the second end of the inflow conduit. A pouch has an interior chamber that defines a volume. The inflow conduit is in fluid communication with the interior chamber of the pouch. An outflow conduit is in fluid communication with the interior chamber of the pouch to permit substantially free flow of fluid from the interior chamber of the pouch and into the outflow conduit, which terminates in an outflow annulus spaced from the pouch.