Abstract: Determining the presence and type of a probe associated with an active implantatable medical device, in particular a cardiac pacemaker and devices having similar pacemaker functionality. This device includes circuits for producing monopolar or bipolar stimulation pulses, selectively with or without disconnection of a connection (S1, S2) to a reference potential, and a circuit for sensing a pulse signal produced by the variation of potential induced on one and/or the other of terminals (RING, TIP) and/or on the metallic case (CASE) in response to an application of stimulation pulses. The device operates to analyze a characteristic of the shape (28), in particular the pulse width, and to deliver an indicator representative of the presence or the absence of a probe. The device also can selectively modify at least one operating parameter of the device according to the delivered indicator.

Abstract: An apparatus for detecting and controlling the presence of a gaseous fluid in relation to a predetermined level of liquid in a vessel, being of the ultrasonic type and comprising a pair of piezoelectric transducers, namely a transmitter and a receiver, capable of being disposed on opposite walls of the vessel. An oscillator provides an electric ultrasonic frequency signal to the transmitter transducer and a comparator compares the electric signal supplied by the receiver transducer with a reference signal for triggering an alarm signal when the disparity between the signals being compared exceeds a predetermined value.The apparatus moreover comprises processing means which periodically interrupt the electric signal sent to the transmitter transducer and which check the presence of an alarm at the output of the above mentioned comparator.