Welding with a pacemaker

If it is needed for a heart rhythm electrical problem vs. just a low heart rate they put in a combo unit pacemaker/defibrillator PM/ICD
You don't want to set one of those off by mistake because it's like getting kicked in the chest by a mule.

Risk vs Reward.
It could save a life for 10 or more years or kill a patient during install.
Messed up part, It keeps going after death and has to be turned off. Believe me...not fun for family.
The survival stats on PMers is very good, those needing ICD not that great