The implant comprises a tubular proximal sleeve, extending between a proximal end and a distal end, and deployable between a contracted configuration and a deployed configuration. Proximal arms each extend between an end connected to the distal end, and a free end positioned past the distal end. At least one proximal arm is elastically deformable between a separating position and an anchoring position, the radial distance between its free end and its connected end being larger in the separating position rather than in the anchoring position. This proximal arm is elastically recalled toward its anchoring position. The implant includes: a first stop, supported by this proximal arm, and a second stop, cooperating with the first stop in the contracted configuration to keep this proximal arm in its separating position, and releasing this first stop in the deployed configuration.
