Abstract: An extracorporeal apparatus is provided for use with an implantable medical device and has a telemetry unit for receiving a telemetry signal transmitted from the implantable device. The extracorporeal apparatus further includes a transmission member disposed downstream of the telemetry receiver for compensating for the signal influence contained in the telemetry signal and effected by a first transmission member in the implantable device for the purpose of interference-free reproduction of a measuring signal received by way of the implantable device in the body, and/or for simulating the signal influence effected by a second transmission member in the implantable device for the purpose of external modelling of the dependency of the device behavior on the measuring signal.

Abstract: A variable rate cardiac pacemaker is adapted to be implanted in a human patient for automatically adapting pacing rate to metabolic need of the patient when the patient is walking in an ascending path, a descending path, or on a level plane. An accelerometer senses the activity of the patient walking, and produces an electrical sensor signal representative of the activity. The accelerometer signal has variable parameters indicative of morphology, including amplitude, of the sensor signal according to status of activity of the patient and to the upward, downward, or horizontal direction of the patient's walking. A pulse generator generates pacing pulses at a variable rate according to an applied control signal to electrically stimulate the patient's heart at a pacing rate which varies according to patient activity.