My 15 Yr Old Grandson Has Suddenly (last 4 Days)

My 15 yr old grandson has suddenly (last 4 days) had several incidents of rapid heartbeat episodes. We've had him to the Drs and are in the diagnosis testing stage. I've argued he spends too much time with the video games. I think I have read video game playing can have an effect/cause heart palpitations. My grandson does not agree of course. Can this be confirmed in any of the diagnostic testing he will be given?