A system for delivering a prosthetic heart valve through the vasculature of a patient, comprising: an elongate shaft having a distal end; a radially expandable member coupled to the distal end of the elongate shaft, the expandable member having an open frame configuration comprising a plurality of struts, the plurality of struts defining an annular supporting surface on the expandable member, the expandable member configured to radially expand from a collapsed configuration to an expanded configuration; and a prosthetic heart valve being collapsible for placement over the expandable member when the expandable member is in the collapsed configuration and wherein the expandable member is expandable to the expanded configuration for deploying the prosthetic heart valve while allowing blood to pass through the expandable member, wherein the expandable member includes a distal end portion and a proximal end portion that are movable relative to one another between a first orientation and a second orientation, wherein the plurality of struts are coupled to the distal end portion and proximal end portion and wherein movement of the distal end portion and proximal end portion from the first orientation to the second orientation causes the plurality of struts to expand radially outwards from the collapsed configuration to the expanded configuration to expand the prosthetic heart valve, wherein a distance between the distal end portion and the proximal end portion of the expandable member is adjustable by a deployment system, and wherein the plurality of struts are pre-formed such that in the expanded configuration of the expandable member, a shape of the annular supporting surface and an expanded shape of the prosthetic heart valve are complementary. an elongate shaft having a distal end; a radially expandable member coupled to the distal end of the elongate shaft, the expandable member having an open frame configuration comprising a plurality of struts, the plurality of struts defining an annular supporting surface on the expandable member, the expandable member configured to radially expand from a collapsed configuration to an expanded configuration; and a prosthetic heart valve being collapsible for placement over the expandable member when the expandable member is in the collapsed configuration and wherein the expandable member is expandable to the expanded configuration for deploying the prosthetic heart valve while allowing blood to pass through the expandable member, wherein the expandable member includes a distal end portion and a proximal end portion that are movable relative to one another between a first orientation and a second orientation, wherein the plurality of struts are coupled to the distal end portion and proximal end portion and wherein movement of the distal end portion and proximal end portion from the first orientation to the second orientation causes the plurality of struts to expand radially outwards from the collapsed configuration to the expanded configuration to expand the prosthetic heart valve, wherein a distance between the distal end portion and the proximal end portion of the expandable member is adjustable by a deployment system, and wherein the plurality of struts are pre-formed such that in the expanded configuration of the expandable member, a shape of the annular supporting surface and an expanded shape of the prosthetic heart valve are complementary.