A vascular implant for replacing a native heart valve comprises a self expanding stent supporting a valve body having leaflets. The stent preferably comprises an anchoring structure configured to prevent the implant from passing through the valve annulus. For delivery, the implant is compacted within delivery device and secured at one end. During delivery the implant is partially released from the delivery device, and positioning of the implant can be verified prior to full release. The implant can be at least partially resheathed and repositioned if desired.