A patient monitor is configured to interrogate an implantable medical
device (IMD) and receive data from the IMD in response to the
interrogation. The data received from the IMD includes electrogram (EGM)
data, which the patient monitor frequency modulates for transmission, in
real-time, onto a conventional telephone line. The frequency modulated
EGM data that is transmitted from the patient monitor may in turn be
displayed, in real-time, at a remote monitoring station in response to
commands provided by a remote (DTMF) signal from a receiving station.