A medical fluid-flow regulating device (100, 100', 100", 400, 500, 600, 700) is described. The medical fluid-flow regulating device (100, 100', 100", 400, 500, 600, 700) comprises a rotor (10, 10', 10", 410, 510, 610, 710) and a flow-regulator element (50, 50") engaged or engageable with each other via a coupling (30, 30', 30", 430, 530, 630, 730) that below a torque and/or fluidic-pressure threshold value allows the flow-regulator element (50, 50") to move upon rotation of the rotor (10, 10', 10", 410, 510, 610, 710) and thereby regulate fluid flow. In particular, the medical fluid-flow regulating device (100, 100', 100", 400, 500, 600, 700) further comprises a blocking unit (40, 40', 40", 440, 540, 640, 740) that above the torque and/or fluidic-pressure threshold value irreversibly blocks the rotor (10, 10', 10", 410, 510, 610, 710) or the flow-regulator element (50, 50") or the coupling (30, 30', 30", 430, 530, 630, 730) between the rotor (10, 10', 10") and the flow-regulator element (50, 50") resulting in irreversible inactivation of the medical fluid-flow regulating device (100, 100', 100", 400, 500, 600, 700). A system comprising the medical fluid-flow regulating device (100, 100', 100", 400, 500, 600, 700) and a method of detecting irreversible inactivation of the medical fluid-flow regulating device (100, 100', 100", 400, 500, 600, 700) are also described.
