A delivery device for percutaneously deploying a stented prosthetic heart valve including a stent frame to which a valve structure is attached, the device comprising: a delivery sheath assembly terminating at a distal end and defining a lumen; an inner shaft slidably disposed within the lumen; a hub projecting from the inner shaft and configured to releasably receive a portion of a prosthetic heart valve stent frame; and a release sheath assembly disposed between the delivery sheath assembly and the inner shaft, the release sheath assembly including a release sheath slidably disposed about the inner shaft; wherein the delivery device is configured to provide a loaded state in which the delivery sheath assembly maintains a stented prosthetic heart valve over the inner shaft and coupled to the hub via the release sheath, and a deployment state in which the distal end of the delivery sheath assembly and the release sheath are withdrawn from the prosthetic heart valve to permit the prosthetic heart valve to release from the hub; wherein the release sheath assembly is configured to proximally retract the release sheath relative to the hub with proximal retraction of the delivery sheath assembly distal end from the release sheath; wherein the release sheath assembly further includes a mounting base connected to the release sheath by at least one biasing member; wherein the mounting base is fixed to the inner shaft proximal the hub; wherein the release sheath assembly is self-transitionable from a deflected state to a normal state, and further wherein a longitudinal spacing between the release sheath and the mounting base in the deflected state is greater than a spacing in the normal state; wherein an outer diameter collectively defined by the biasing member in the normal state is greater than a diameter of the lumen of the delivery sheath assembly. a delivery sheath assembly terminating at a distal end and defining a lumen; an inner shaft slidably disposed within the lumen; a hub projecting from the inner shaft and configured to releasably receive a portion of a prosthetic heart valve stent frame; and a release sheath assembly disposed between the delivery sheath assembly and the inner shaft, the release sheath assembly including a release sheath slidably disposed about the inner shaft; wherein the delivery device is configured to provide a loaded state in which the delivery sheath assembly maintains a stented prosthetic heart valve over the inner shaft and coupled to the hub via the release sheath, and a deployment state in which the distal end of the delivery sheath assembly and the release sheath are withdrawn from the prosthetic heart valve to permit the prosthetic heart valve to release from the hub; wherein the release sheath assembly is configured to proximally retract the release sheath relative to the hub with proximal retraction of the delivery sheath assembly distal end from the release sheath; wherein the release sheath assembly further includes a mounting base connected to the release sheath by at least one biasing member; wherein the mounting base is fixed to the inner shaft proximal the hub; wherein the release sheath assembly is self-transitionable from a deflected state to a normal state, and further wherein a longitudinal spacing between the release sheath and the mounting base in the deflected state is greater than a spacing in the normal state; wherein an outer diameter collectively defined by the biasing member in the normal state is greater than a diameter of the lumen of the delivery sheath assembly.