The device has an electrode line which is connected at an end to a control unit and/or to the unit configured to detect electromagnetic interference fields comprising stimulation timer (250). The detection unit evaluates the detected signals as non-physiological signals for a specifiable time period, and/or for a next specified time period the stimulation unit is placed in an asynchronous operating state in which a wearer of the device is asynchronously stimulated, when non-physiological signals and/or electromagnetic interference fields are detected. An independent claim is included for method for operating implantable medical device.
