Patent ID: 7908005

Claim:
Medical system, comprising: an implantable medical device configured for in vivo implantation in a subject, said implantable medical device being configured to provide an in vivo medical therapy to the subject according to therapy parameters set by a control unit in the implantable medical device; a predetermined number of electrode pairs connected to said implantable medical device and configured to be arranged at or within the subject; electric field excitation signal generators in said implantable medical device, connected to the electrodes, that apply alternating voltage excitation signals at a preset frequency to the electrodes of each electrode pairs to generate an electric field through the heart between the electrodes of the respective electrode pairs; a signal receiver in said implantable medical device that receives a signal representing the voltage potential difference between a voltage potential of at least one of the heart electrodes used as detecting electrode and a reference electrode, a voltage potential being related to the generated electric field, and that thereafter generates a potential difference signal, representing said voltage potential difference; a signal controlling and processing unit in communication with said signal receiver, that is provided with and processes the detected potential difference signal in order to determine cardiac parameters representing heart activity; and said control unit also being in communication with said signal controlling and processing unit and being supplied with said cardiac parameters by said signal controlling and processing unit, said control unit being configured to set or adjust said therapy parameters dependent on said cardiac parameters.