For your ex-, consider this giant bleeding gummy heart candy or maybe some of these chocolate hearts from "Pushin' Daisies."
For your sweetheart, though, it's probably better to stick with this heart locket that opens to reveal the heart's four chambers.
Me? Well, the abstract has appeal and for that, I'm leaning toward getting one of these t-shirts. The only problem is, the shirt's probably better for those interventional cardiology "plumber" types.