The present disclosure relates to delivery devices for transcatheter stented prosthesis loading, delivery and implantation. The delivery devices provide a loaded delivery state in which the stented prosthesis is loaded and compressed over the delivery device. The compression of the stented prosthesis can be adjusted with one or more elongate tension members, which extend around the stented prosthesis and proximately to an actuation and release assembly that can be provided as part of a handle assembly. The delivery device can be manipulated to adjust tension in the tension members to permit the stented prosthesis to compress, self-expand, and ultimately release from the shaft assembly. In some embodiments, the tension in one or more tension members is adjusted with one or more actuation and release assemblies.