These are such great episodes. The Enterprise one specifically is amazing. We so often see our valiant crew save Earth, but they almost never sacrifice their morals to do so.
For Archer, with practically all of humanity in the balance, how could he not fuck those guys over?
Pace makers keep you from dying so they're sort of on a different level of need. Also, if corps did planned obsolescence on one, you're probably not around to buy another.
If they were invented today, they would definitely have a predatory subscription model for "monitoring" your heart, or require occasional maintenance at cost to the end user.