The assembly has a simulation screw probe (10) with a helical anchoring screw (14) axially extending a head of the probe. A detachable catheter (26) implants the probe and includes a single preformed tube having two surfaces (38, 40) with two curves in absence of solicitation. The curves auto-orient a distal end of the tube in a target vein with the head in a retracted position and maintain an axis of the screw in a direction of an epicardium during combined displacement and screwing movement of the head to a deployed position.
