This list was sent to me by a prospective customer. It is by no means exhaustive. So, always check and double check with your own cardiologist about what you can and cannot use.
"My pacemaker "manual" contains the following as cautions against/causes of EMI (electromagnetic interference):
Electrical appliances in poor condition or not grounded correctly.
Electrical equipment that produces a great deal of energy, like industrial generators.
Metal detectors and security systems used in stores and airports.
High voltage transmission lines and equipment, arc or resistance welders, induction furnaces.
Communication equipment, such as microwave transmitters, linear power amplifiers, or high powered amateur transmitters.
TENS units, which are electrical nerve and muscle stimulators.
Therapeutic radiation, such as cancer radiation therapy.
Electrosurgical cautery, which can inhibit the operation of pacemakers.
Magnets, large heaters, and radio transmitters.
Magnetic resonance imaging (MRI) scans, which can severely damage a pacemaker, when you are in or near an MRI room. "
Again, always check and double check with your cardiologist about anything you have questions with regarding your pacemaker.