Electromagnetic Inferference (EMI)

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It is important to be aware of medical procedures and common items that may create electromagnetic interference (EMI) with your device. Items that give off electromagnetic signals may cause your device to mistake those impulses for the signals coming from your heart.


A CRT-P may respond to EMI by delaying its pacing. A CRT-D may respond by delivering a shock that you don’t need or not providing a shock that is needed.

EMI is generally temporary and dependent on how close you are to the item giving off the signals.

Refer to this list for general items to avoid or view a printer-friendly PDF. Contact your doctor if you have any questions about how a specific type of equipment will interact with your device.

Medical Procedures

Not Recommended

  • MRI/MRA scans
  • Microwave Diathermy

Check with Your Doctor Before Undergoing the Following Procedures

  • Acupuncture with Electrical Stimulus
  • Cardioversion
  • Electrocautery
  • Electroconvulsive Therapy
  • Electrolysis
  • Endoscopic Procedures:Colonoscopy/Gastroscopy
  • Hyperbaric Therapy
  • Iontophoresis
  • Interferential Current Therapy
  • Laser/Lasik Eye Surgery
  • Lithotripsy
  • Radiation Therapy
  • Radio Frequency Ablation
  • Ultrasound, Therapeutic
  • Transcutaneous Electrical Nerve Stimulation (TENS)
  • Transurethral Prostate Therapy

No Known Risk

  • Acupuncture with no Electrical Stimulus
  • Bone Density Scan
  • CT Scans
  • Dental drills and Ultrasonic Scalers
  • Diagnostic X-ray
  • Electrocardiogram
  • External Counter Pulsation
  • Fluoroscopy
  • Mammography (Position Emission Tomography (PET)
  • Ultrasound, Diagnostic

Personal and Office Technology

Not Recommended

  • Magnetic mattresses or chairs
  • Electrical equipment that is in poor condition or improperly grounded

No Known Risk, But Follow Precautions as Noted

  • AM/FM radios
  • Bingo game magnetic wands
  • CB and Ham radio
  • CD/DVD players
  • Cell phones*
  • Copy machines
  • Cordless phones*
  • Hand-held massagers*
  • Hearing aid
  • Electric blankets
  • Electric toothbrushes
  • Electric razors*
  • Electric invisible fences
  • Fax machines
  • Global positioning system (GPS)
  • Hair dryer*
  • Heart rate monitors
  • Heating pads
  • iPods and MP3 players
  • Laser tag games
  • Pagers
  • Patient alert devices
  • Laptop/desktop computers
  • Personal digital assistants
  • Printers
  • Remote controls - TV, garage door, stereo, camera/ video equipment
    Scuba Diving (up to 200 feet)
  • Slot machines
  • Stereo speakers*
  • Tanning beds
  • TVs and VCRs
  • Video games

* Do not placed directly over device

Security and Anti-theft Systems (Airports and Retail Stores)

No Known Risk, But Follow Precautions as Noted

Inform airport security personnel you have an implanted device and show Medical Device ID card

Metal detectors and Electronic Article Surveillance systems are generally safe, but do not linger when you pass through them

If the alarm sounds (it may not), it only means that the system detected the metal in your device.

Security personnel may use a handheld wand. If so, it is important that you ask them to perform the search quickly and to avoid holding the wand over your implanted device for a prolonged period of time.


Household Items

Not Recommended

  • Electrical appliances that are in poor condition or improperly grounded

No Known Risk, But Follow Precautions as Noted

  • Air purifiers
  • Battery-powered cordless power tools
  • Blenders
  • Clothes dryers
  • Convection ovens
  • Corded drills and power tools*
  • Electric can openers
  • Electric knives
  • Electric ovens and stoves
  • Food processors
  • Gas ovens and stoves
  • Gas-powered tools*
  • Hot tubs/whirlpool baths
  • Lawn mowers*
  • Laser level
  • Leaf blowers
  • Microwave ovens
  • Portable space heaters
  • Snow blowers
  • Soldering iron
  • Stud finder
  • Vacuum cleaners
  • Washing machines

* Keep 12 inches from device

Industrial Equipment

A variety of industrial equipment produce EMI of sufficient field strength and modulation characteristics to interfere with proper operation of the pulse generator. These include, but are not limited to: arc welders; induction furnaces; very large or defective electric motors; and internal combustion engines with poorly shielded ignition systems.