Unconfirmed media reports say Nancy Guthrie's pacemaker stopped syncing with her Apple devices. Here's what that means.

The Pima County Sheriff's Department previously highlighted the significance of Nancy’s pacemaker in the investigation, revealing additional details about its role in an approximate timeline of her la

Nancy Guthrie’s 2 a.m. pacemaker spike on the day she vanished could mean that the elderly woman was involved in a heart rate-surging struggle with her possible captors, a lead cardiologist speculated Thursday.