The invention provides methods and systems for introducing a delivery device in the heart at or near the apex of the heart, wherein the delivery device includes a prosthesis, advancing the prosthesis to the target site, and disengaging the prosthesis from the delivery device at the target site for implantation. Specifically, the present invention provides valve replacement systems for delivering a replacement heart valve to a target site in or near a heart. The valve replacement system comprises a trocar or other suitable device to penetrate the heart at or near the apex of the heart, a delivery member that is movably disposed within the trocar, and a replacement cardiac valve disposed on the delivery member. The delivery member may further comprise mechanical or inflatable expanding members to facilitate implantation of the prosthetic valve at the target site.
