This implant comprises an endoprosthesis having an axis which can be spontaneously deployed in a radial manner between a compressed configuration and a dilated configuration. The implant comprises at least one radial runner which comprises a separation surface which extends radially with respect to an outer surface of the endoprosthesis and a member which can be deployed away from the axis. The runner is arranged so as to delimit a confinement housing which extends between the separation surface and the outer surface and a radial spacer which is defined by the separation surface and the deployable member. When the implant is retained in a state of radial compression, the maximum radial width of the housing is less than the maximum radial width of the spacer which is not equal to zero.