Systems and mechanisms for deploying a docking device for a replacement heart valve

A delivery device for a prosthetic implant, the delivery device comprising:

• a delivery catheter having a first lumen;
• and
• a pusher tool comprising:
• a pusher disposed within and axially movable relative to the first lumen, the pusher having a distal portion, a proximal portion, and a second lumen extending from the proximal portion to the distal portion;
• a locking mechanism;
• a sealing cap releasably coupling the locking mechanism to the proximal portion of the pusher;
• and
• a retrieval line extending through the second lumen from the locking mechanism, through the sealing cap, and to the prosthetic implant to connect the prosthetic implant to the pusher tool,
• wherein the locking mechanism comprises a rotatable member connected to the retrieval line, the rotatable member having a first position and a second position, wherein the first position corresponds to a minimum amount of retrieval line that extends from the locking mechanism, and wherein the second position corresponds to a maximum amount of retrieval line that extends from the locking mechanism.