"Although qualified as a doctor, [Rune Elmqvist] chose to invent medical equipment instead. In 1949, while working at Elema-Schonander (later Siemens-Elema), in Stockholm, he applied for a patent for the Mingograph, the first inkjet printer.
[...]
One of Elmqvist’s other inventions [was] the first fully implantable, rechargeable pacemaker.""