This device includes a hollow support delimiting, in the vicinity of a distal end, a transverse retention opening. It further includes an endoprosthesis which can be deployed between a state retracted against the support and an expanded state. The device further includes a filamentary connection forming a clamping ring surrounding the endoprosthesis and forming a loop engaged in the support through the retention opening. A retention rod mounted to be movable in the support, and the retention rod has a hook for retaining the loop. The displacement of the retention rod from a release position to a retention position brings about the tightening of the clamping ring.
