They weren't talking to his doctor. They got records from a third party (the pacemaker manufacturer).
Now, the interesting bit that you can't discern from TFA is whether the pacemaker data was specifically downloaded for purposes of the investigation or if the information came out on routine interrogation. I'm guessing the former since you only check the pacer if you think there is a problem or perhaps twice a year. If the downloading of the data was compulsory, that opens some entertaining legal questions.
Pacemakers are typically tested quarterly when in working order, monthly when in low battery state when the device supports transtelephonic or inductive testing. Yearly in-person checkups are also typically done. (Transtelephonic: Patient wears a device on each hand or wrist, device communicates with remote servers over a POTS system. Inductive: Patient places a device over pacemaker and initiates remote reading, device communicates over phone, cellular, network, or internet to remote servers.)
Some "remote monitoring" platforms support automatic daily to 3-week intervals and send results to the manufacturer accordingly. (Source, PDF)