In various embodiments, a system for delivering an implantable device inside a body cavity includes: 1) a core cannula 2) an access sheath 3) an injection apparatus for filling the implantable device with one or more fluids and 4) expanding members operatively connected to the core cannula for preventing the core cannula from advancing through a body orifice once the core cannula and expanding members exist the access sheath. According to particular embodiments, a distal end of the core cannula is pre-attached to the implantable device through a device locking member. In one or more embodiments, upon assessment, an injection apparatus is removed using an injection apparatus handle, the implantable device is detached from the core cannula via a device deployment handle (to be implanted), and the access sheath is removed.