Abstract: The invention relates to an endoprosthesis (1), in particular a vascular or cardiac endoprosthesis (1), having a body (2) and also one or more thrombogenic elements (3) that are fixed to the endoprosthesis (1) and that are able to extend a distance away from the body outside the latter. The endoprosthesis comprises means (33) for selectively retaining the thrombogenic elements near the body (2). The release of the one or more thrombogenic elements, after the endoprosthesis has been fitted in place by a conventional method via a sheath, promotes thrombosis.