It killed a kid in my sports class growing up as well. Dropped like a stone, cardiac arrest, couldn't be resuscitated. After that they had a 'heart health' mobile ekg come to the school once a year for people who wanted a check up which I thought was a great idea. They actually diagnosed a few people, I think at least two others with WPW but also a more common condition where the wall of the heart thickens which can also be dangerous during exercise.