Patent ID: 7650185

Claim:
A method carried out by a satellite implantable medical device for being awakened from a sleep state by a primary implantable medical device, the satellite implantable medical device including a wake-up sensor, a control module, a physiologic sensor, a power supply, and a communication module , the method comprising: waiting in a sleep state, wherein only sensing circuitry of the wake-up sensor is energized and powered on for detecting and processing an output voltage from the wake-up sensor; detecting, by the wake-up sensor, the presence of an electromagnetic wake-up field generated by the primary implantable medical device; responsive to detecting the presence of the electromagnetic wake-up field, prompting power control circuitry coupled to the power supply to supply electrical power to the control module and the communication module, causing the control module and communication module to change from the sleep state to an active state; and wherein, in the active state, the control module causes the physiologic sensor to activate and sense at least one physiologic parameter, and the communication module to wirelessly transmit the at least one sensed physiologic parameter to the primary implantable medical device.