Ok. So something was wrong the night before. That's similar to Pebbles before she died. You're saying heart attack, was she highly stressed out within her last week of life? If you're thinking a heart attack because you picked her up, unless you picked her up wrong like suddenly, I doubt that would have been the cause. My Thistle was very feral when I got her, and I pick her up everyday with her kicking, screaming, and more and she's been fine. (She's actually much calmer now.) Thistle was about four months old when we got her.