If simple scaling isn't doing it for you, you could experiment with some of the Distort effects like Bulge or Mesh Warp to alter the shape of heart.
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I am totally new to this. I think scale can help to change the size as I wanted. But I don't have experience in making it look like real beats. The way it came out very edgy/hard motion and not smooth. I guess something like Easy would help? I don't know.