My MIL, having A-Fib, although was unable to use a Pacemaker, was placed in counseling for other methods.
As I took her to these different "classes" they often talked about the changes and advancements in Pacemaker technology including the ability to recharge / diagnose and even adjust thru the RF coupling thru and under the skin to help the patient.
Couldn't help her at the time, but the changes are present, they don't go into a lot of details but they are RF devices and are subject to interference. So as you may have already guessed, Bluetooth technology as well as CD RF charge coupling phone inductive charger units - they do emit EMI which can be a concern. Xrays, MRI and similar non-invasive and those energy levels they use, are the biggest danger to them.
Yes, there' an App for that now too.