A valve prosthesis and a system for delivering a valve prosthesis are described herein. The system can include a core member and an engagement mechanism for releasably engaging a radially expandable valve anchor of the valve prosthesis along the core member. The engagement mechanism can include a pin assembly slidably coupled to the core member and a nose cone including a lock component slidably coupled along the core member to permit the valve anchor to disengage from the pin assembly.
