https://www.msn.com/en-us/news/us/investigators-hope-to-catch-signals-from-nancy-guthrie-s-pacemaker/ar-AA1WHdKA
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The app on Guthrie's phone, which was left at her home in Tucson, picked up data transmitted from her pacemaker via Bluetooth. But pacemakers still attempt to transmit that data, even if someone is separated from their mobile device, according to digital forensics experts..."