I don't know why, but I really love visible heartbeats. I think they might be among my favorite things in cardiophilia. Somehow the more visible they are, the better.
But more than that, there's something especially erotic about the body reactively twitching/moving a little or thrusting, forwards or otherwise, in sync to the throbbing force with a heartbeat sound just eminating. A cherry on top would be that person shuddering/stuttering to every beat from the force of their heart, not to mention every contraction feels so good.
I've seen such, um, animations before, with or without a heartbeat, and for some reason I've always enjoyed it.


















