An implantable device (1) for injecting and/or drawing fluid either in an organ or vessel of the body of a human or animal patient and the device comprising a housing (2) with a chamber (2A) connected to a catheter, the catheter is connected either to the organ or vessel or to the compartment. The housing (2) has a proximal wall (4) and a distal wall (5) between which a lateral wall extends. The housing (2) has a puncture area (7) able to be pierced by a hollow needle (14) for injecting and/or drawing fluid in the chamber (2A). The puncture zone (7) extends on the proximal wall (4) and the lateral wall.