As part of the original tests for the DoH on the interference of Rf transmitters with medical devices I was given some mobile phones and police and ambulance walkie-talkies with which to upset anything I could lay my hands on.
I got an old APC4164 external pacemaker and put a 50ohm resistor straight across the terminals - no leads (aerials). Every time I pressed the PTT button of a walkie-talkie the needle flicked in to Sense, even from 7meters away.
I demonstrated this to a Home Office person saying that repeated transmissions made the pacemaker think the heart had a steady rhythm so it did not need to pace. He was rather concerned as the new police radio that he was working on was a packet system, transmitting in bursts. He said that if they were guarding a prisoner/patient they were not allowed to turn the radios off in case they needed to call for urgent back up.
Moral of the story - do not commit a crime if you have a dickie ticker... but if the prisoner is in the bed next to you.......or even in the same ward.
PS Dickie Ticker is a character in the new Carry On film