I don't know if this will help or not, but over here at work we experienced the loss of a very dear collegue. He was both physically fit and young (about 38 YO), and with no clear or obvious predisposition to heart disease or cardio-vascular disease. He passed away rather suddenly while on a business trip during a routine jog. His cause of death was related to heart (mechanical) failure. Apparently something (underlying cause still unknown) threw his system off. The closest thing that we have to some sort of clue is a rather strange one. During the period of less than a year, three hard-drives on his work laptop had to be replaced. I don't know if there is any sort of a connection here, but the coinsidence is rather peculiar. I'm wondering if there is any sort of connection between the "circuitry" inherent in our brains (signals, synaptic impulses, etc.) and the use/overuse of all the digital technology that is everywhere to be found.   For what it's worth,   -Rob