A pacemaker is not an artificial heart. It's a little implantable device that connects to the heart through electrodes and helps regulate the beating of the heart in people whose hearts beat too quickly or too slowly. There are also implantable cardioverter-defibrillators that help detect and then shock potentially deadly cardiac arrhythmias.

Smoking with either of those devices is not ideal, according to my husband. Patients do it anyway, but it'd be better if they did not. Cannabis can be particularly irritating to cardiac arrhythmias and often alters cardio-electrical conduction. Any cardio-electrophysiologist worth his salt would advise patients with pacemakers or defibrillators to refrain from smoking anything, cigarettes or cannabis alike. (Still, they don't always follow that advice.)

I have a cardiac arrhythmia for which an implantable defibrillator hasn't yet been invented. (They're working on a couple of them now.) That's a large part of why I'm a cannabis advocate but not a smoker; it really messes with my heart electricity in a bad way.