You're right, there's not much info on the wanderguard technology ... but thanks for raising that issue.
I would assume it would be the same principle as with security devices used in department stores (a magnetic thingamajig). For which case magnets (of this intensity anyway) should not be placed 6 inches near the pacemaker. It "may" cause interference but not a fatal malfunction. The pacemaker resumes normal activity after the magnet source is removed. If the resident sleeps with his hand (with the wanderguard) resting on his chest all night

.... that could be a problem???
Anyhow, this pacemaker site have some info on gadgets which may or may not cause interference. Hmmm, I always thought microwave ovens do...
http://www.medtronic.com/brady/patient/quicklook.html
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