Electric Blankets

Do you use an electric blanket? We do all the time when it is really chilly at night. A few years ago, they warned against them due to the electric currents or something I can't even remember. Now I heard yesterday that someone said that every time your electric blanket kicks on during the night, it also jump starts your heart. My brother, the joker, said "good, if I die, it will jolt me awake." But I wonder if there is any truth in it??? Actually, I am not going to worry about it as we have been using electric blankets for years as we like the heat turned down at night and you seem to sleep better in the cooler air around you.