Listen to Demi Lovato on iHeartRadio

Demi Lovato released her brand new single "Heart Attack" Sunday night. This is a fitting title considering the song was supposed to be premiered on "On Air with Ryan Seacrest" March 4th, with Demi in the studio. 

Talk about heart attack! Demi surprised her fans by premiering and releasing the new single a week ahead of schedule!

Check out her new single, available now on iTunes: 

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