Demi Lovato's 'Heart Attack' AHA Performance Was Encouraged by Org

Demi Lovato sang a song of hers that certainly might've seemed inappropriate at an event all about heart health -- but as it turns out ... that's not how it was received in the room.

Sources with direct knowledge tell TMZ ... Demi singing her track "Heart Attack" earlier this week at the American Heart Association's Go Red for Women Red Dress Collection concert might be getting roasted online ... but it was the exact opposite from folks there in the moment.

We're told the AHA fully backed Demi's decision to belt out this tune -- in fact, they encouraged her to sing the song -- which you can see in the clip making the rounds.

As for why our Demi sources feel like it wasn't offensive or out of touch -- as many on X have suggested -- we're told it's because Demi has reclaimed this song and its meaning ... especially in light of her own health scare following an overdose in 2018.

In the wake of that, Demi has sung this song with new significance behind it ... and it's that same sentiment that was carried over in her performance Wednesday -- one that our sources tell us got rave reviews in the moment from those in the room.

We're told Demi also acknowledged her connection to the song ahead of the performance ... telling the audience: "[T]his song has many parallels for me, my journey and a reminder for all of us in the room just how strong the mind-heart-body connection truly is."

Anyhoo, this should hopefully clarify any confusion from those who were scratching their head about the song choice ... not only was it the right song, but her heart was in the right place.