Patent ID: 7450990
Filing Date: 2008-11-11
Classification: A61N

Abstract:
1. A device for delivering electrical stimulation pulses to body tissue through a stimulation electrode, comprising: energy storage means for providing electrical stimulation energy to the stimulation electrode from an energy source; a first switch with which the energy storage means is switchably connected to the energy source for charging the energy storage means; an electrode connection for connecting the stimulation electrode to the device for delivering electrical stimulation pulses to the body tissue; a second switch with which the energy storage means is switchably connected to the electrode connection for the delivery of a stimulation pulse; means for monitoring stimulation outcome during a time interval between 0 milliseconds and 10 milliseconds after said delivery of a stimulation pulse, wherein said means for monitoring stimulation outcome does not use active measurement pulses from an active current source or an active voltage source; a short-circuit switch with which the electrode connection, after delivery of the stimulation pulse, is switchably and at least indirectly connected to a ground potential such that, in the case of a connected and implanted electrode, a capacitance can be discharged by way of the body tissue wherein the capacitance includes at least one Helmholtz capacitance produced on the surface of the stimulation electrode in conjunction with surrounding body fluid or the body tissue; and a control unit which is connected to at least the first switch, the second switch, and the short-circuit switch for switching the respective switches and which is adapted to separate the electrode connection from the energy storage means after delivery of the stimulation pulse and at least indirectly connect the electrode connection to the ground potential; wherein the means for monitoring stimulation outcome during said time interval is connected to the electrode connection and is adapted to detect a drop in a voltage during said time interval at the capacitance or a rise in a short-circuit current during said time interval at the capacitance, said drop in voltage or said rise in short-circuit current being representative of a characteristic drop in a myocardium impedance of said body tissue indicating stimulation success.