In a method and system for establishing a wireless communication session between an implantable medical device IMD and a home monitoring device, the home monitoring device frequently sends communication-initiating signals to an IMD arranged within the body of a patient for establishing a communication session between the monitoring device and the IMD. In order to save energy, RF telemetry circuitry of the IMD is normally set in a low-power, idle mode. Occasionally, the RF circuitry will leave the low-power mode and enter an active mode in which it is able to detect a communication-initiating signal transmitted by the monitoring device. When a communication-initiating signal is detected, the IMD will respond accordingly to the monitoring device and a communication session will be established. In the present invention, the telemetry circuitry of the IMD will be controlled to wake up from low-power mode and enter an active detection mode independently of the transmission of the communication-initiating signals from the monitoring device. Hence, the external monitoring device will frequently transmit communication-initiating signals, but the IMD will only detect a wakeup signal when leaving its low-power mode and entering active mode at a predetermined instant of time.
