The present invention is directed to an implantable medical device and a method for power management for power efficient use of RF telemetry during, for example, conditions where long periods of continuous monitoring of the device and the patient is desired such as during MRI procedures. A protocol module adapted to, at receipt of a low power protocol indication, activate and use a low power protocol for communication between the device and external units. The protocol module is capable of switching between different communication protocols including a low power communication protocol and a default RF communication protocol depending on, for example, whether continuous long-term monitoring of the patient is performed. During the low power communication protocol, the protocol module is adapted to select parts of stored electrophysical and/or hemodynamical signal waveforms for telemetric transmission and to create communication packages having a predetermined length using the selected parts of the electrophysiological and/or hemodynamical signal waveform. Further, a transmitter is instructed to transmit the communication packages at predetermined transmission intervals and the telemetry module is instructed to power down the transmitter or set the transmitter in a lowest possible activation state during intermediate periods between the transmission intervals.
