Devices that May Interfere with ICDs and Pacemakers

Several types of devices and machinery may interfere with implantable cardioverter defibrillators (ICDs) and pacemakers.

The electromagnetic waves generated by these devices can keep your ICD or pacemaker from functioning properly. Try to avoid them, or at least minimize your exposure to them.

Your health care professional can advise you about specific devices and machinery to avoid. But, in general, the following can cause interference:

Anti-theft systems (also called electronic article surveillance or EAS)

Interactions with EAS systems, such as those found at department stores, are unlikely to cause clinically significant symptoms in most patients.

  • Don’t linger near an EAS system longer than is necessary.
  • Be aware that EAS systems are often hidden or camouflaged near the exits for businesses such as retailers.
  • Don’t lean against the system’s sensors.

Metal detectors for security

Interactions with metal detectors are unlikely to cause clinically significant symptoms in most patients.

  • Don’t stand near the metal detector any longer than is necessary.
  • Don’t lean against the structure of the system.
  • If scanning with a handheld metal detector is necessary, tell the security personnel that you have an ICD or pacemaker, and request an alternative form of inspection, such as a pat down. If they insist on using a handheld metal detector, ask them not to hold the wand near your device any longer than is absolutely necessary.

See the Transportation Security Administration (TSA) advisory page(link opens in new window) for those traveling with implanted devices.

Cell phones

Wireless transmissions from the antennae of phones available in the United States are a very small risk to ICDs and even less of a risk for pacemakers.

  • Technology is rapidly changing as the Federal Communications Commission (FCC) makes new wireless frequencies available.
  • Newer cellphones using these new frequencies might make ICDs and pacemakers less reliable. The wireless industry is investigating that possibility.
  • Keep your cell phone at least six inches away from your ICD or pacemaker by using it on the ear opposite where your device was implanted. Avoid keeping your cell phone in your front chest pocket.
  • If you use walkie-talkie radios or Bluetooth technology, ask your health care professional what safe distances are for these.


Most headphones contain a magnetic material that can interfere with ICDs and pacemakers. Both earbud and clip-on headphones can cause interference. So, bear in mind:

  • Keep headphones at least six inches away from your ICD or pacemaker.
  • Don’t allow someone wearing headphones to rest his or her head on your chest.
  • Don’t place headphones in your breast pocket.
  • Don’t drape headphones around your neck so that they hang on your chest.


Citizen’s band (or CB) radios and amateur “ham” radios pose little or no risk to pacemakers. But they can affect how an ICD performs.

  • CB radios or ham radios under three watts should be kept at least six inches away from your ICD.
  • CB and ham radios operating on three-15 watts should be kept at least 12 inches from your ICD.
  • CB and ham radios operating on 15-30 watts should be kept at least two feet from your device.

Power-generating equipment, arc welding equipment and jumper cables

Follow your doctor’s instructions about being around such equipment. In general, stay at least 2 feet away.


Magnetic fields in magnets in devices and machinery can inhibit pulse generators for ICDs and pacemakers. In ICDs in particular, magnets can activate a switch prohibiting the ICD from delivering vital signals such as lifesaving shocks.

If you have an ICD or pacemaker, avoid close or prolonged contact with magnets or their magnetic fields. Keep magnets at least six inches from where your device is implanted.

Of course, you may not always know if you have come into proximity with machinery that uses a magnet. It’s best to err on the safe side. If you feel any interference, move away from the source, or turn it off if possible.

Avoid magnet therapy that may call for you to wear magnetic bracelets or necklaces near your implantation site. Also avoid magnetic pillows and magnetic mattress pads, which can be found in some adjustable or smart beds; these may interfere with your ICD or pacemaker.

Ab stimulators and electronic body fat scales

Both devices likely interfere with an ICD or pacemaker. Avoid them if you have an implanted device.

Gas-powered equipment and gasoline ignition systems

Components within the ignition systems of gas-powered engines can cause interference in some cases. If you have an ICD, stay at least 12 inches away from the ignition system of a vehicle or other gas-powered equipment.

This does not prohibit you from using a key to start a car – the ignition components are far enough away from the car’s front seats.

Portable car battery chargers

If you use such a charger, keep the components at least 12 inches away from where your device is implanted.

Electric fences and electrical pet containment systems

The electromagnetic fields used by such systems can disrupt ICDs and pacemakers. The risk increases with proximity to the signals and the length of time spent near them. Avoid or limit your exposure to such systems. Ask your health care professional about safety if you work with or spend time around these systems.

Also, avoid or limit your exposure to transformer boxes. The electromagnetic field emanating from them can interfere with ICDs and pacemakers.

Medical alert systems and fall detection pendants

Contact customer support of your medical alert system provider to see if their product might pose a risk to your pacemaker or ICD.

Medical procedures that may pose a risk

Some medical, diagnostic and cosmetic procedures may interfere with the operation of your ICD or pacemaker. The following are of particular concern:

Extracorporeal shock-wave lithotripsy (ESWL)

The noninvasive treatment uses hydraulic shocks to dissolve kidney stones. If you have an ICD, speak with your health care professional before undergoing ESWL.

Many pacemaker patients may be eligible for ESWL, provided the pacemaker is evaluated and reprogrammed before and after treatment if necessary. After ESWL, those with pacemakers will need to follow up with their doctor over several months to ensure that the pacemaker continues to work properly.

Patients with certain kinds of pacemakers implanted in the abdomen should avoid ESWL. Before considering ESWL, discuss the procedure with your doctor, including the implications for your implanted device.

Magnetic resonance imaging (MRI)

Magnetic resonance imaging is a noninvasive diagnostic tool that uses a powerful magnet to produce images of internal organs and functions.

ICDs and pacemakers contain metal, and therefore, are not normally allowed near MRI machines. The strong magnetic field can interfere with the function of implanted devices.

Still, some types of implanted devices don’t preclude MRIs. Or the benefits for the MRI may outweigh the risks. As always, talk with your doctor about the specific considerations for your implanted device.

Always let imaging technicians, such as those supervising an MRI, know about your implanted device.

Radiofrequency ablation (RFA) or microwave ablation

Both ablation procedures are used to treat arrhythmias. Both use a long, thin tube called a catheter to eliminate abnormal electrical signals in the heart by administering energy to a specific part of the heart tissue.

If you have an ICD, you should consult with your health care professional about the risks of ablation.

Ablation is often performed before a pacemaker is implanted. If an ablation procedure is warranted even though you already have a pacemaker, your doctor may evaluate and reprogram your pacemaker before and after the procedure. The radio frequencies used during ablation may alter your pacemaker’s function. Studies have shown that most implanted pacemakers are not adversely affected.

High-frequency, short-wave or microwave diathermy for physical therapy

This medical procedure uses high-frequency, high-intensity electromagnetic waves for physical therapy. One type of this therapy is not recommended for those with an ICD or pacemaker under most circumstances. Speak with your health care professional before undergoing this type of therapy.

The electromagnetic waves used in diathermy may interfere with either device’s pulse generator. This can permanently damage your implanted device.

Radiation therapy

This therapy used for cancer treatment can damage the circuitry of ICDs and pacemakers. The degree of damage is unpredictable – and may vary with different systems – but the risk builds with increased radiation.

ICDs have been shown to be more sensitive to radiation therapy interference than pacemakers. If you have an ICD and radiation therapy is still warranted, your implanted ICD should be shielded from the radiation as much as possible. Your ICD may need to be relocated if it lies directly in the targeted radiation field.

Transcutaneous electrical nerve stimulation (TENS)

This procedure uses electrical signals to relieve acute or chronic pain by placing a medical device with electrodes on the skin and connecting it to a pulse generator.

If you have an ICD, TENS treatment may be acceptable, provided certain precautions are taken. TENS interferes with some types of ICDs, but not with others. Note: TENS is not recommended for use on the torso.

When it comes to pacemakers, most studies have shown that TENS rarely inhibits bipolar pacing. TENS may sometimes briefly interfere with unipolar pacing, but this can sometimes be addressed by reprogramming the pulse generator. Speak with your health care professional before undergoing this treatment.

CT and CAT Scans

Specialized diagnostic X-rays called computed tomography (CT scan) or computed axial tomography (CAT scan) provide multiple images of areas inside the body. Some CT or CAT scanning devices may interfere with ICDs, but the probability is extremely low. Before having a CT or CAT scan, discuss precautions and considerations beforehand with your health care professional and the imaging technician.

X-rays, such as those used in CT or CAT scans, don’t appear to interfere with pacemakers. Still, always alert the imaging technicians that you have a pacemaker implanted before undergoing a CT or CAT scan.


This procedure stops bleeding during surgery. If you have an ICD, you and your doctor should carefully weigh the benefits and risks. The procedure may be acceptable if certain precautions are taken.


This procedure removes unwanted body hair or tissue.

If you have an ICD, speak to your health care professional before having this procedure. Your device manufacturer may also provide important recommendations.

ICD patients should be prepared to provide a note from their physician before electrolysis can be performed.

Devices that pose little or no risk

In general, consumer appliances and electronics don’t affect the performance of ICDs and pacemakers. On rare occasions, some of these devices may inhibit pacemakers by a single beat. But the pacemaker’s regular signals are quickly restored.

Even though these devices may pose little known risk, still strive to keep all motors and antennae at least 6 inches away from your ICD or pacemaker. Speak with your health care professional about whether it’s safe to use any item.

Household appliances and electronics

  • Electric shavers
  • Electric blankets
  • Heating pads
  • E-readers
  • Electronic tablets
  • Microwave ovens
  • Kitchen appliances, such as mixers, blenders, toasters and coffeemakers
  • Ionized air filters
  • Computers
  • AM/FM radios
  •  TV transmitters and remotes
  • Home wireless devices, such as modems, routers and headsets
  • Video game wireless controllers
  • TV and stereo speakers
  • Bluetooth® wireless technology, including headsets
  • Hair dryers
  • Irons
  • Hand-held back massagers
  • Electronic weight scales

Garage, shop and lawn equipment

  • Garage door openers
  • Hedge trimmers
  • Weed trimmers
  • Leaf blowers
  • Electric lawn mowers
  • Electric drills (including cordless drills)
  • Power saws, routers and sanders
  • Laser levels
  • Stud finders
  • Light metalworking tools (including soldering irons)
  • Keyless entry car remotes
  • Battery-powered flashlights
  • Metal detectors for recreational use - stay 2 feet away from the detector head
  • GPS devices
  • Radio-controlled toys and devices

Office machinery and electronics

  • Computers
  • Printers and scanners
  • Photocopiers
  • Security badge scanners

Other devices with little risk

  • Salon-style hair dryers
  • Tanning beds
  • Hot tubs
  • Casino slot machines
  • Massage chairs and massage pads
  • Low voltage power lines (often found in residential areas)

Medical procedures that pose limited risk

Several medical procedures are permissible for those with ICDs or pacemakers. Still, be sure to discuss any possible risks with your doctor before undergoing such treatments.

In general, the following pose limited risk if precautions have been taken:

  • Heart rate monitor
  • Electrocardiogram (EKG or ECG)
  • Echocardiogram
  • Acupuncture, with or without electrical stimulus
  • Ultrasound diagnostic imaging
  • Hyperbaric oxygen therapy
  • Elective cardioversion
  • Stereotaxy
  • Dental ultrasonic scalers, cleaners and drills (Note: Some patients may feel a pacing increase during dental drilling.)
  • Diagnostic radiation (such as screening X-rays and mammography)
  • Electroconvulsive therapy (such as used for certain mental disorders)
  • Pills swallowed for video endoscopy
  • Laser surgery
  • Pet emission tomography (PET scans)
  • Bone density tests using X-rays, as well as ultrasounds on the heel or hand
  • Devices designed to treat sleep apnea
  • Deep brain and spinal cord stimulator implantation

Carry your wallet ID card

If you have an ICD or pacemaker, always carry a wallet ID to alert emergency personnel about your device in case you’re incapacitated.

Always tell health care professionals, including dentists and diagnostic imaging technicians, that you have an implanted device. Also make the on-site nurse or doctor at your place of work aware that you have an ICD or pacemaker.