Demi Lovato unveils 'Heart Attack' lyric video - watch

Demi Lovato has unveiled the lyric video for her new single 'Heart Attack'.

On Friday (March 1), the singer asked her fans on Twitter to tweet lyrics from 'Heart Attack' before she could 'unlock' the lyric video.

Speaking about her upcoming new album, the X Factor USA judge said: "For a while, I could tell that when people would talk to me they knew my story. I think I've opened up more on this album.

"My life began to evolve and I started to grow. These are songs about the celebration of life and how rewarding it can be. This is what this album is about."

'Heart Attack' will be available for US download from Monday (March 4). No UK release date has been announced.

Lovato's last album Unbroken, which featured hit songs 'Skyscraper' and 'Give Your Heart a Break', was released in 2011.

Watch the lyric video for 'Heart Attack' below:

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