“If a person was in a physical struggle, that might have created a rapid heartbeat … the pacemaker would have detected that and potentially reported it,” Dr. Jonathan Reiner, who was former vice president Dick Cheney’s cardiologist, chillingly told CNN.

Arizona authorities previously said the 84-year-old’s implanted medical device stopped syncing with her Apple devices, including a watch and her iPhone, around 2 a.m. Sunday – close to the time police believe she was abducted from her Tucson home.

Nancy was last seen the night before when she was dropped home by her son-in-law at about 9:45 p.m.

When investigators reached the home hours after she was reported missing, around noon, the devices were still inside the house.

The disturbing revelation comes as the desperate search for Guthrie continues into its fifth day Thursday.