Heroine has a heart condition (flatlined but hero's voice brought her back)

[Lucy]

Hey:)! So I think that's a YA the heroine is in high school and has a heart condition(I think the hero is her teacher but not sure). Towards the end of the book I remember reading that her heart literally broke..But at the same time she might have had a breakup with the hero. Anyways one think I'm certain about is that she was in the ER and flatlined and the hero went in and by hearing his voice she came back to life. Pretty sure they lived happily ever after and went on to have kids

Thanks for any help
Lucy

[Lobstergirl, au gratin]

When did you read it?
Paper, ebook, other format?

[Lobstergirl, au gratin]

Lucy, are you still looking for this or did you find it?