Demi Lovato's 'Heart Attack' hits No. 1 on iTunes in the U.S. and Canada

Demi Lovato's "Heart Attack" has hit No. 1 on iTunes in the U.S. and Canada in the song's first week of release. The song (which was released on Feb. 25, 2013) is the first single from Lovato's fourth album, whose title and release date are to be announced. In January 2013, Lovato tweeted that she has been recording the album.

"Heart Attack" was originally scheduled for release on March 4, 2013, but due to an unauthorized leak of the song, Hollywood Records pushed up the official release date of "Heart Attack" a week earlier.

Lovato tweeted on Feb. 25, 2013: "THIS IS ONE OF THE BEST DAYS OF MY LIFE!!!!!!!!!! ALL BECAUSE OF YOU GUYS!!!!!!!!! THANK YOU!!!!!!!!! 14 hours after releasing my new single.... YOU MADE IT #1 ON iTUNES IN 9 DIFFERENT COUNTRIES INCLUDING THE USA!!!!!!!!!!!!!!!! AHHHHH!!!"

Then on Feb. 27, 2013, she tweeted: "Day 3 for Heart Attack and still number 1 on iTunes?!?! You guys are incredible. So blessed!!!"

On Feb. 26, 2013, Lovato went on the syndicated radio show "On Air With Ryan Seacrest" to promote "Heart Attack" and play a snippet of the song.

(Click here to watch Part 1 of the "On Air With Ryan Seacrest" interview.)

(Click here to watch Part 2 of the "On Air With Ryan Seacrest" interview.)

(Click here to watch the official lyric video for "Heart Attack.")

In the interview, Lovato explained the meaning of "Heart Attack" and her personal connection to the song: "There have been times you've been hurt or, for me, other situations where I felt abandoned in my life. And when you open your heart to somebody, it's a risk. And this song is about taking that risk or the feelings that come from it. It's me deciding whether or not to take that risk and my guard's up."

Seacrest, who conducted the interview, did not directly ask Lovato about her current relationship status, but he did ask her what she did on Valentine's Day. Lovato is rumored to be back together with her on-again/off-again boyfriend Wilmer Valderrama. As previously reported, Lovato and Valderrama were seen having a romantic dinner and cuddling with each other on Valentine's Day (Feb. 14, 2013) at Takami Sushi & Robata Restaurant in Los Angeles, after she had performed earlier that day at the grand opening of Topshop Topman at The Grove shopping mall in Los Angeles. Valderrama and Lovato were also seen together on Feb. 13, 2013, at a party to celebrate the opening of Topshop Topman in Los Angeles.

When Seacrest tried to get Lovato to say what she did on the evening of Valentine's Day, she made it clear that she didn't want to answer the question by first avoiding a direct answer to it by changing the subject. After Seacrest kept pressing her and asking the question, she responded: "I open up so much to my fans about my personal life, but some things just have to stay sacred." Seacrest then dropped the line of questioning about her love life.

Lovato became a judge on "The X Factor" U.S. in May 2012. Since then, her music career has soared to new heights. "Give Your Heart a Break," the second single from her third album, "Unbroken," reached No. 1 on Billboard's Top Pop Songs radio chart in 2012 and peaked at No. 16 on Billboard's Hot 100 chart. It's been the biggest hit of her career so far, but "Heart Attack" could surpass "Give Your Heart a Break," based on how well the song is selling in its first week of release. The official Billboard Hot 100 chart debut for Heart Attack will be announced on March 6, 2013.

In several recent interviews, Lovato has been saying that she does not know yet if she will continue to be a judge on "The X Factor" U.S. in 2013. So far, "The X Factor" executive producer Simon Cowell is the only judge confirmed for the show. The replacements for Britney Spears and L.A. Reid have not yet been named.

Lovato won the 2013 People's Choice Award for Favorite Celebrity Judge. "The X Factor" U.S. won the 2013 People's Choice Award for Favorite Reality Show.

As previously reported, she also has two concerts scheduled for March 2013: Universal Studios Orlando in Florida on March 2 and Smart Araneta Coliseum in Manila, Philippines on March 20. On Feb. 27, 2013, she hosted a Twitter Q&A with Universal Studios Orlando.