Patent ID: 8554318

Claim:
An active implantable medical device for one of cardiac stimulation, resynchronization, and defibrillation, comprising: an electronic circuit for a detection/stimulation of a cardiac activity; a first sensor for detecting a first magnetic field positioned in proximity to the device; a second sensor for detecting a second magnetic field positioned in proximity to the device; means for activating said second sensor in response to said first sensor detecting the first magnetic field and for inactivating the second sensor otherwise; and means for placing the electronic circuit in a safekeeping operating mode in response to the first sensor detecting the first magnetic field and the second sensor detecting the second magnetic field; wherein the means for placing the electronic circuit in a safekeeping mode further comprises: means, upon detection of the first magnetic field by the first sensor, for placing the electronic circuit into a magnet mode of operation without cardiac detection, and for activating the second sensor; and means, upon detection of the second magnetic field by the second sensor, for inhibiting a component of the device that is sensitive to the second magnetic field, and for placing the electronic circuit into a modified magnetic mode by modifying at least one parameter of said magnet mode of operation; wherein the magnet mode of operation is a mode in which the electronic circuit produces stimulation pulses at a first predetermined frequency, correlated to a charge level of a power supply of the device; and wherein the modified magnet mode is a mode in which the electronic circuit produces stimulation pulses at a second predetermined frequency, independent of the charge level of the power supply of the device.