Songfacts®:

• Explaining to NME how this song is an "old idea amalgamated with a brand new one," lead singer Pete Doherty told NME that the revision sparked competition between himself and fellow co-frontman Carl Barât. "We pulled out all the stops really on the songwriting front," he said. "Carl and I had a lot to prove to each other as songwriters."
• The song's music video was directed by photographer and film maker Roger Sargent. It finds Doherty and Barât in a viewing box repeatedly forcing drugs and booze on dummy versions of themselves while members of the public watch on, baying for more.
  
  Sargent said of the clip, "In 'Heart Of The Matter,' Peter and Carl reflectively talk about the damage and abuse they have caused themselves over the years, openly mystified that they have survived thus far. It's a catharsis, a bleak, bold and brave one."
  
  "To that end, when we talked about making the video for the song we all felt it had to be similarly honest. The unsettling subjects could not be shied away from. On the contrary, these had to be faced head on."