Abstract: A method for monitoring a patient for rejection reactions to an implanted organ is provided with an implantable telemetry measuring unit with electrodes that can be implanted in the organ. An electric current is passed through the body tissue via two current electrodes. The impedance of the body tissue through which this current is flowing is determined with two measuring electrodes. Each of the measuring electrodes annularly surrounds one and only one current electrode. The electrodes are embedded in a support element such that they project from this support element only with their front end.

Abstract: To monitor a patient for rejection reactions of an implanted heart, a permanent magnet is implanted epicardially in the heart wall and a magnetically active semiconductor element, preferably a Hall generator, is implanted endocardially. Movement of the heart wall results in changes in the distance between the permanent magnet and the semiconductor element. An implantable component supplies the semiconductor element with current and measures the signal generated by the movement of the heart wall. The measured values are transmitted electromagnetically out of the body by the component and recorded extracorporeally, and stored for data transmission.