In most cases, once the threat is gone, the body returns to normal. In cases of people who have been scared to death, the result of what the fear does to their body is what kills them. The rush of the adrenaline, elevated heart rate and other key portions of the fight or flight response are what really kill them. In many cases, these instances are medically considered and cataloged as “sudden heart failure.” There are hundreds of cases of this happening and even more close calls. Apparently, people who are predisposed to or living with certain illnesses are more prone to being scared to death. There are even famous cases that remain officially unsolved as the only answer investigators can come up with is that the victim was scared to death.