Abstract: A pressure and heart movement sensor for a heart stimulator, includes an electrode system for implantation with an electrode cable containing at least two electrical conductors leading to electrode poles. A measurement device is arranged to measure an electrical quantity between the electrical conductors, which quantity varying according to the pressure applied to the electrode cable. Alternately, the electrode cable contains at least one electrical conductor, and the measurement device is arranged to measure the impedance between the conductor and ambient medium and to deliver an output signal, which varies according to the impedance measured, when the electrode cable is subjected to pressure.

Abstract: A system for administering medical therapy includes an implantable medical apparatus containing an audio transmitter and an audio receiver for respectively transmitting and receiving extracorporeally audible audio signals. The system also includes an extracorporeal programming and control apparatus, which also includes an audio transmitter and an audio receiver. The medical apparatus can thus communicate directly, in both directions, with the extracorporeal programming and control apparatus by means of audio signals. Such communication can take place, for example, via a telephone line, so that the patient in whom the medical apparatus is implanted need not be physically present at the location of the extracorporeal programming and control apparatus in order to establish communication.

Abstract: An implantable heart defibrillator and a method for defibrillating a heart, employ a shock pulse generator for delivering a defibrillation shock to a heart, the delivered energy being mechanical. The shock pulse generator includes an electromechanical energy converter which generates, e.g., pressure, by means of a piezoelement, in a pressure chamber. Pressure is transmitted by a fluid in an electrode devised like a hydraulic line to a balloon-like electrode head in contact with heart tissue. The generated pressure causes the electrode head to expand and deliver a mechanical shock to the heart corresponding to the pressure.

Abstract: A method and apparatus for calculating a parameter for a physiological function wherein, given a measurement signal influenced by more than one physiological function parameter, signal components of the measurement signal arising from a parameter not of interest are filtered out such that a period duration inversely proportional to the respective current frequency of the parameter not of interest is continuously identified and a mean value of the measurement signal is continuously formed over the identified period duration.

Abstract: Defibrillation of a heart ensues using a charging capacitor connected via a controllable switch arrangement to electrodes arranged in the region of the heart, the switch arrangement being operated to discharge across the heart tissue. In order to limit the initial current to a value not significantly exceeding the minimum value necessary to effect defibrillation, the controllable switch arrangement includes two contacts between which a contact maker, for example a mercury drop, is disposed, which is deformable under the influence of an electro-mechanical transducer. The transducer is arranged such that the contact maker connects the two contacts to one another given a prescribed excursion of the electro-mechanical transducer and, given a change of the excursion departing from the prescribed excursion, varies the electrical resistance between the contacts.

Abstract: An implantable medical apparatus for stimulating a heart at a variable stimulation rate dependent on the respiratory rate, tidal volume, heart rate and stroke volume includes a measurement apparatus which measures impedance around the heart, a filter unit which splits the impedance signal into high-frequency and a low-frequency signal portions and two analyzers which respectively evaluate the signal portions and which emit the four parameter values as output signals. The product of respiratory rate times tidal volume is formed in a control apparatus. This product corresponds to respiratory minute volume, and the product of heart rate times stroke volume corresponds to cardiac output. Cardiac output is multiplied by a constant, and respiratory minute volume is subtracted from the product thus formed. The resulting different is equal to zero when blood oxygenation is optimum. The control apparatus controls the stimulation rate on the basis of the magnitude and sign of the difference.

Abstract: An inductive motion sensor (MS) connectable to a subject (16), the motion sensor having a coil (4) and a magnet member (3) movable relative to the coil (4). The magnet member (3) has at least four magnetic poles, whereby the number of south poles (S) is equal to the number of north poles (N). The pole strength of the magnetic poles is dimensioned and the magnetic poles are located on the magnet member (3) such that the magnet member (3) is situated in a neutral equilibrium position in a uniform magnetic field with respect to the forces exerted on the magnetic poles by the magnetic field.