An approach is disclosed for improving ventricular function of a patient's heart. According to one embodiment, the system includes a pouch that defines a chamber dimensioned and configured to simulate at least a portion of a heart chamber. The pouch has a sidewall portion extending from an inflow annulus and terminating in a closed distal end spaced apart from the inflow annulus. A generally cylindrical outflow portion extends from the sidewall portion of the pouch and terminating in an outflow annulus thereof to provide for flow of fluid from the chamber through the outflow annulus. A valve is operatively associated with the inflow annulus of the pouch to provide for substantially unidirectional flow of fluid through the inflow annulus and into the chamber.