Tornados can scare you to death!

Craig Maire II

Here is a statement I took off the NCDC website concerning 2 fatalities that occurred during the La Plata Maryland tornado:

A 54-year-old man died in his car from an apparent heart attack at the intersection of Route 301 and Route 6 in downtown La Plata. The third victim, a 72-year-old woman, died of a heart attack in Waldorf after being frightened by the tornado.

Two of the three people who died in the La Plata Maryland tornado didn't even get struck by the tornado or any of its flying debris but simply were scared to death! I have heard of this happening in other tornados and am wondering if anyone else has any info concerning deadly heart attacks and tornados?
The only fatality that occurred in my (former) home county in E TN during the Nov. 10, 2002 outbreak was a volunteer firefighter who died when he was going to check on his family after the tornado hit.
Would be interesting to see more data on this.