Anyone travel with an LVAD heart pump?

I had no idea what an LVAD was so I looked it up. That is quite the device and based on what I read only used for people in rather bad shape. Not going to ask any personal questions, but I'd be more concerned about the travel itself for that person versus the device. But having said that, looks like it operates off rechargeable batteries that are in an external pack. So the device itself isn't powered by the generator, just the batteries are charged. Doesn't seem like that would be much of a problem, but I think I'd want a couple of spare battery packs just in case.