Implantation device for implanting a prosthesis (110) in a vessel (1), including a balloon (128) and a dilation catheter (120) for supplying fluid to the balloon (128), the dilation catheter (120) having a proximal end, a distal end (124) and a distal part designed to be introduced into the vessel (1), characterized in that the distal part includes a bend (123) and also an upstream portion (121) and a downstream portion (122) that are contiguous to the bend and that are arranged between the bend and, respectively, the proximal end and the distal end (124).
