While I'm all for the advancement of science, am I the only one who feels that concealing a vital sign of life is more or less a bad idea? If a person stops breathing, one of the first things a medical responder will do is check for a pulse. I imagine this will be important for the target market.

I could see these also being desired by prisoners wishing to escape confinement by hiding in an exiting truck or perhaps enemy combatants who hope to not be detected by heartbeat sensors(if those even really exist).