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

A former FBI agent says Nancy Guthrie’s Apple Watch data could show possible distress, movement, or a struggle before investigators say her pacemaker app disconnected overnight.

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

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.

Pima County Sheriff Chris Nanos provided the public with updates on Tuesday, February 3, regarding the disappearance of Savannah Guthrie’s mom, Nancy Guthrie, including the report that her pacemaker had stopped syncing with her Apple devices.

A man who had a pacemaker fitted when he was just nine years old has gone on to complete two marathons. Kieran Cooper, of Blackpool, Lancashire, was born with a heart condition and was never allowed to play sports as a child. He said he found this incredibly difficult but "thankfully there is a different mindset nowadays".

Some of the most recent evidence in the desperate search for Nancy Guthrie, the 84-year-old mother of “Today” host Savannah Guthrie, is also among the case’s most disturbing: purported ransom notes sent to media outlets.

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