Meaning of この胸に突き刺さったなら?


I am trying to comprehend Japanese a little better through translating songs,
this is from Kirinji's "Killer Tune Kills me" and from what I understand
"この胸に" would be translated to "in this chest" but then I can't make sense of
the rest, from "突き刺さ" I believe it refers to something like the chest getting
stabbed, but "ったなら" I can't find what it means exactly.




[突き刺さる](https://jisho.org/word/%E7%AA%81%E3%81%8D%E5%88%BA%E3%81%95%E3%82%8B)
is an _intransitive_ verb meaning "(for a knife, stick, etc.) to
penetrate/cut/stick into something". 突き刺さった is its past/perfect form (aka the
"ta-form"). なら is a conjunctive particle meaning "if". See: [Japanese
Conditional Form なら](https://www.tofugu.com/japanese-grammar/conditional-form-
nara/)

胸 is a word that means "chest", "breast" or "heart (in the psychological
sense)" depending on the context. Here, "heart" is the natural translation.

> この胸に突き刺さったなら  
>  If it stuck into my heart, ...

Of course, this doesn't mean a murder has occurred. This is a metaphorical
expression that describes that you were deeply moved or struck by the killer
tune.

