There's also the ability to stick AEDs on drones, which relies on the member of the public reporting the heart attack to use it, but can make them available to that person much more quickly than instructions about where to find the nearest publicly-accessible AED.

You can obviously also have a lot more defibrillator drones available across a city than jetpack-equipped paramedics. I've seen it as a concept, not sure how many are in use and what their success rates have been.