Cardiac pacemakers are miracles of modern medicine and technology – pocket-sized machines continuously monitoring and regulating your heartbeat for 8-12 years. Unfortunately, younger patients can expect to replace their battery-powered device several times over their lifetime. Oddly enough, we used to have pacemakers with a projected service life of multiple human lifespans – and they were nuclear-powered.
Really?
- The first implantable plutonium-powered pacemaker was developed during the late 60’s and actually implanted in a patient in 1973. Overall, 139 patients received nuclear pacemakers.
- Zalman Shapiro invented the nuclear pacemaker. He’s still alive at 94 and may have secretly given plutonium to Israel, enabling their weapons program.
- Up until 2007, the nuclear pacemakers had outlived all patients they were fitted in, except for one. Cancer rates were not increased, thanks to the device’s exceptional shielding.
Who killed the nuclear pacemaker?
There are many valid reasons why atomic-powered devices went out of fashion:
- Although invented at the height of the Atomic Age, patients (and doctors) disliked the idea of having plutonium planted inside them.
- Battery-powered devices quickly reached acceptable battery life while costing less than a third of their nuclear counterparts.
- Lithium pacemakers can be disposed of easily. Plutonium-238 requires special treatment.
- Later during their service life, the longevity of atomic pacemakers actually turned into a drawback. Newer pacing algorithms were being developed by manufacturers, whereas patients with nuclear devices had to make do with 20- or 30-year-old technology.
Do nuclear pacemakers have a place in the future?
- We may never see another plutonium-powered pacemaker. However, there are other promising nuclear alternatives to the battery.
- Betavoltaic cells generate energy from beta particle radiation. Tritium can be used as fuel, which is cheaper and safer than plutonium. Indeed, betavoltaic pacemakers using promethium were developed and tested in the 70s.
- Unfortunately, beta radiation destroyed the electronic circuits of the day, so complex pacing algorithms couldn’t be implemented. This is no longer an issue.
- Younger, pacemaker-dependent patients are ideal candidates for betavoltaic pacemakers – each time they undergo replacement of their pacemaker, they are at risk of infection and lead displacement.
Take home messages
- Nuclear pacemakers truly existed; one may still be ticking inside a 69-year old lady.
- Plutonium-powered devices quickly gave way to battery-powered solutions.
- Betavoltaic pacemakers are nuclear-based devices that could come handy in cases where a simple pacemaker is expected to be required for more than 30 years.