 " Heart " was first broadcast on February 14 , 2012 in the United States on Fox . It received a 2 @.@ 8 / 8 Nielsen rating / share in the 18 – 49 demographic , and attracted 6 @.@ 99 million American viewers during its initial airing , a significant decrease from the 3 @.@ 3 / 9 rating / share and 7 @.@ 81 million viewers of the previous episode , which was broadcast on February 7 , 2012 , and the lowest rating of the third season to date . In Canada , however , viewership increased , and 1 @.@ 72 million viewers watched the episode on the same day as its American premiere . It was the thirteenth most @-@ viewed show of the week , up two slots and over 9 % from the 1 @.@ 57 million viewers who watched " The Spanish Teacher " the previous week . 
