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

Information about Nancy Guthrie's pacemaker helped authorities piece together a new timeline in her kidnapping. Can the ...

As the search for Savannah Guthrie's mother, Nancy, continues, a cardiologist explains how pacemakers work and if they can be used to track a missing person's location.

One part of the investigation into the disappearance of "Today" show host Savannah Guthrie's mother focuses on the missing ...

Dr. Srihari S. Naidu speaks with Parade to answer all our questions about pacemakers.

Nancy Guthrie’s pacemaker reportedly stopped syncing with her Apple devices predawn Sunday morning – as the Arizona sheriff leading the missing person case called a surprise press conference for late ...

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 ...

A law enforcement source told Fox News Digital that the 84-year-old's pacemaker last synced with her Apple devices around 2 a ...