FAQ

Bioimpedance analysis (BIA) is a commonly used method to estimate body composition by sending a low-level electrical current through the body. Manufacturers have traditionally recommended that patients with implanted cardiac devices like pacemakers, implantable cardioverter defibrillators (ICDs), or cardiac resynchronisation therapy devices (CRT-Ds) avoid BIA due to concerns about potential interference.

However, a small study published in 2012 evaluated 20 patients with heart failure who had either an ICD or CRT-D device implanted. The researchers performed BIA on these patients while monitoring their devices in real time. They found no evidence of any interference from the BIA, including no telemetry disruption, no oversensing on the device leads, and no symptoms experienced by the patients.

While this study suggests BIA may be safe in patients with certain cardiac implants, the researchers noted that further confirmatory studies with larger patient groups are still needed. As always, it’s best to consult your doctor or cardiac electrophysiologist before undergoing any procedures or tests if you have an implanted cardiac device.

There is theoretically a risk of damage to the ICD/lead from an electric shock from UK mains buts it’s extremely unlikely and it would be classed as a very low risk. 

This is because the current tends not to pass through the ICD/lead but passes through the body to the ground using the shortest and quickest route e.g. hand, up the arm, down the torso, and out through the leg. The majority of devices also have circuitry built in to protect them against electrical surges. 

The advice would be to go to the hospital if a person was feeling unwell, otherwise, it would be recommended that a person contact their local device clinic and request a device check which could be performed as a remote transmission. This would pick up on any rare issues caused and provide reassurance.

Maintain at least the recommended distance between the item and your heart device:

12-Inch Distance

Car/Motorcycle – from components of ignition system
Electric Fence
Electric Pet Containment Fence – from buried wire and indoor antenna
Transformer Box (green box in yard)

2-Foot Distance

Beach Comber Metal Detector – from search head
Induction Cooktop Stove

Not Recommended

Ab Stimulator
Electronic Body Fat Scale
Magnetic Mattress Pad/Pillow

Maintain at least a 6-inch distance between the item and your heart device:

Electric Grocery Cart/Golf Cart – from motor
Electric Kitchen Appliances – hand-held (electric mixer or knife)
Electric Shaver – corded
Electric Toothbrush Charging Base
Exercise Bike – from magnet in wheel
Hair Dryer – hand-held
Hand-held Back Massager
Magnetic Therapy Products
Radio-Controlled Items – from antenna
Sewing Machine/Serger – from motor
Small Magnet (household magnet)
Speakers
Tattoo Machine
Treadmill – from motor
Ultrasonic Pest Controller
Vacuum Cleaner – from motor

The electromagnetic energy generated by a chainsaw is similar to other electric and liquid fuel-powered tools. If electromagnetic interference occurs with your heart device and you experience symptoms such as becoming dizzy or lightheaded, a running chainsaw may present a higher risk of injury to you than other power tools.

Yes, but extreme caution should be excised at all times.

Follow the safety precautions below to minimize the risk of interfering with your heart device while using a chainsaw.

• Maintain a 6-inch distance between the motor of an electric chainsaw and your heart device.
• Ensure the equipment is properly grounded.
• Maintain a 12-inch distance between the components of the ignition system of a liquid fuel-powered chainsaw and your heart device. Also, it is better to use one that is built with the spark plug located away from the handgrips.
• Immediately stop cutting and turn off your chainsaw if you start feeling lightheaded, dizzy, or you believe your implantable defibrillator has delivered a shock
• Do not work on the engine while it is running
• Do not touch the coil, distributor, or spark plug cables of a running engine

It is recommended you avoid using welding currents above 160 amps. Follow the safety precautions below to minimize the risk of interfering with your heart device while welding with currents under 160 amps.

Welding Safety Precautions

Limit welding to currents less than 160 amps
Work in a dry area with dry gloves and shoes
Maintain a 2-foot (60cm) distance between the welding arc and heart device
Keep the welding cables close together and as far away as possible from your heart device. Place the welding unit approximately 5 feet from the work area.
Connect the ground clamp to the metal as close to the point of welding as possible. Arrange the work so the handle and rod will not contact the metal being welded if they are accidentally dropped.
Wait several seconds between attempts when having difficulty starting a weld
Work in an area that offers firm footing and plenty of room for movement
Work with an informed person who understands these suggestions
Immediately stop welding and step away from the area if you start feeling lightheaded, dizzy, or you believe your implantable defibrillator has delivered a shock

Since welding equipment may temporarily affect the normal operation of your heart device, any decision you make to use this equipment should be made in consultation with your heart doctor. Your doctor can advise you as to the degree of risk these responses pose for your medical condition.

Aprons or vests will not effectively shield your pacemaker or implantable defibrillator from the electromagnetic energy generated by welding equipment.

Unlike most other household power tools, welding with currents above 160 amps may have a higher tendency to temporarily affect the normal function of your pacemaker or implantable defibrillator.

Even though most electromagnetic fields in the home environment will rarely affect the function of a pacemaker or implantable defibrillator, it is recommended you keep any item containing magnets away (at least 6 inches/15 centimeters) from your pacemaker or implantable defibrillator.

The reason for this is because there is a small magnetically activated switch built into the electronics of pacemakers and implantable defibrillators. This internal switch is designed to close when a magnet of enough strength is placed over it.

When the internal switch is closed in the pacemaker, the pacemaker paces the heart at a continuous pre-set rate (which could be different than the rate your doctor programmed).

When the internal switch is closed in an implantable defibrillator, it prevents it from delivering treatment therapies.

You may not always know if an item has a magnet in it. However, if you use household items as they are intended, and they are properly maintained, they should have no effect on your heart device. This includes microwaves, kitchen appliances, cordless phones, radios, televisions, video games, CD players, hair dryers, electric shavers, electric toothbrushes, electric blankets, leaf blowers, lawn mowers, garage door openers, computers, and small shop tools.

If you mistakenly place a magnet too close to your heart device, simply move the item away.

Removing the magnet returns the pacemaker or implantable defibrillator back to its previous, normal programming.

The use of magnetic mattress pads and pillows is not recommended since it would be difficult to keep a 6-inch (15 centimeter) separation from your heart device.

Given the short duration of security screening, it is unlikely that your heart device will be affected by metal detectors (walk-through archways and hand-held wands) or full-body imaging scanners (also called millimetre wave scanners and 3D imaging scanners) such as those found in airports, large venues and courthouses.

The metal case of your heart device could set off a metal detector. To minimize the risk of temporary interference with your heart device while going through the security screening process, avoid touching metal surfaces around any screening equipment. Do not stop or linger in a walk-through archway; simply walk through the archway at a normal pace.

If a hand-held wand is used, ask the security operator not to hold it over your heart device and not to wave it back and forth over your heart device. You may also request a hand search as an alternative. If you have concerns about these security screening methods, show your device ID card, request an alternative screening, and then follow the instructions of the security personnel.

Yes. Anti-theft detectors in stores and libraries generate electromagnetic fields that can “sense” embedded “tags” on merchandise. It may be possible, under unique circumstances, for these fields to temporarily affect the operation of your heart device. Significant effects from interference are unlikely if you pass “normally” through the detectors. It is recommended that you:

Be aware of anti-theft detectors
Walk through at a “normal” walking speed
Don’t linger close to the detection system equipment. If you are near an anti-theft system and feel symptoms, promptly move away from the equipment. Your heart device will resume its previous state of operation when you move away from the equipment.

Prior to any scan, your doctor should determine whether there is an effect on your heart device.

See our MRI Compatibility page for more information.

Your doctor should discuss all potential benefits and risks of an MRI scan with you. Present your ID card to the doctor recommending the MRI scan. If needed, your doctor can seek more information from the manufacturer of your ICD.

You should speak with your doctor regarding this situation.

Many modern ICDs and leads are compatible with MRI scanners and many are retrospectively approved.

See our MRI Compatibility page for more information.

Many modern devices and leads are now MRI compatible but older ones are often not.

You can get more information about how to check by going to our MRI Compatibility page.

When using a powered hand tool, whether battery-powered or electric, keep the tool’s motor at least 6 inches away from your device.

Yes, you can use a heating pad. They have no known effect on ICDs.

Yes, it could. Your mobile phone, as well as any accessories containing magnets (such as earbuds or cases with magnetic clasps) need to be kept at least 6 inches away from your device.

In most cases, you can undergo laser hair removal. Check with your doctor and the manufacturer of your ICD.

Always carry your heart device ID card. This card is helpful if your heart device sets off a metal detector or a security system.

Any transmitting sound amplifier should be kept at least 6 inches from your ICD.

It is possible to have both an ICD and a vagal nerve stimulator. Some precautions may be necessary, however. Consult with your doctor.

Phones, which use wireless signals, have electromagnetic fields around them. Some of these fields may affect the normal operation of your heart device. Your phone should be kept at least 6 inches away from your device.  When using a mobile phone, it is best to hold it to the ear that is farthest away from your heart device. Also, is a good idea to avoid carrying your phone in a shirt pocket that is close to the ICD.

No, your phone should be kept at least 6 inches away from your device. Cell phones, which use wireless signals, have electromagnetic fields around them. Some of these fields may affect the normal operation of your heart device. When using a mobile phone, it is best to hold it to the ear that is farthest away from your heart device.

Wireless battery chargers that don’t require an AC plug-in are used to charge items such as cell phones, music players and tablets. When using this type of charger, keep at least 6 inches between the charger and your ICD.

When using an AC charger of up to 100 amps, such as those used to recharge a car battery, keep your ICD at least 12 inches away from the charger.

For some electric vehicles, there may be safety precautions when charging the battery. For example, you may not be able to sit in the vehicle while it is charging. Check with the car’s manufacturer for guidelines.

Yes, it is safe to drive an electric car if you have an ICD or other heart device.

Cosmic rays consist of high-energy radiation that strikes the earth from space. Most of these flares and rays are absorbed in the atmosphere and are unlikely to affect an ICD once they reach the ground.

If you work on power lines, you may encounter interference with your ICD’s operation. Consult with your employer and your doctor.

Standing under large power lines at ground level should not affect your ICD. However, stay out of any fenced areas such as substations.

Yes. You can work on your car as long as there is no medical reason to avoid working around engines. You should, however, keep at least 12 inches between your ICD and parts of the car’s ignition system.

You should keep at least 12 inches between your ICD and parts of the car’s ignition system.

You may walk through security devices and they should not affect your ICD. Simply walk through the area at a normal pace, but don’t stand or linger nearby. Always carry your heart device ID card. This card is helpful if your heart device sets off a metal detector or a security system. If a handheld wand is used, ask security personnel to avoid holding it over or waving it back and forth over your heart device.

Using a vibrator poses no risks. Just make sure the vibrator is in good working condition and has no electrical problems.

A momentary shock will not permanently damage your ICD. A memorable (longer) shock may cause some ICD settings to be reset to nominal values. Your doctor can restore your individual settings in the clinic.

You don’t need to give up cattle rustling if you have an ICD. Both line-powered and battery-powered electric fences pose low risk because they are energized for a very short time – about once a second. If you accidentally touch an electric cattle fence, the momentary shock will be startling, but it will not permanently damage your ICD. The shock may temporarily prevent the pacemaker capabilities of the ICD from sensing a slow heart rhythm.

Hoover Dam policy recommends that people with implanted ICDs do not tour the dam because of its 60Hz magnetic field. The magnetic environment within other hydroelectric plants, however, may differ so check with them to see what their policies are for people with ICDs. Being around such strong magnetic fields may result in your ICD delivering an inappropriate shock. Tour a non-hydroelectric dam if you want to see how great quantities of water are held back through the marvels of human engineering.

MRI equipment generates large magnetic fields and radio waves that may interfere with ICD operation. Check with your doctor to see what precautions, if any, you should follow when working around MRI machines.

Items that generate or use electricity or transmit wireless signals have electromagnetic fields around them. Some of these fields may affect ICD operation. Remember that most items used in everyday life are not likely to affect your ICD. However, if you are concerned about equipment in your work environment, ask your employer to measure electric field intensity limits that may interfere with your ICD or to hire an outside firm to do so.

Yes, you can use a urinary monitor that includes a magnet. Just remember to keep the tether magnetic strap and battery compartment of the monitor at least 6 inches away from your ICD.

No, joy buzzers or other tools of mirth won’t hurt your ICD. But your prankster probably doesn’t know that…hint, hint.

Pet shock collars for electric pet fences, including remote controls and bases with antennas, should be kept six inches away from your heart device.  Buried wires should be at least 12 inches from your ICD.

Yes! Good idea. For a gas-powered lawn mower, just be sure to stay at least 12 inches away from the ignition system while it’s operating. We hope you win a really weird trophy.

E-readers have wireless transmitters to work on data networks, so we recommend keeping them 6 inches away from your ICD. So, no, you shouldn’t fall sleep with them snuggled up close. That’s getting a little too attached to your technology anyway.

Items that contain magnets, such as bingo wands, mechanic’s extractor wands, magnetic bracelets, clasps, or chair pads, magnetic therapy products, stereo speakers or earphones, and handheld massagers can temporarily affect the operation of your implanted heart device. We recommend you keep items containing magnets at least 6 inches (15 centimeters) away from your device.

Yes, you can use mobile phones. However, mobile phones may cause electrical interference with your heart device when the phone is turned on and held too close to your heart device. Also, some accessories for mobile phones contain magnets that may cause interference, such as earbuds or cases with magnetic clasps. Any effect is temporary, and simply moving the phone or accessory away will return the heart device to its previous state of operation.

Definitely. Just keep them 6 inches away from your ICD.

Get your yard maintenance on. It’s fine to use a powered lawnmower as long as you keep some distance between the running mower and your ICD. For electric motors, stay 6 inches away. If you’re using a gas-powered mower, keep the ignition (spark plug area) at least a foot away from your heart device.

Always carry your heart device ID card. This card is helpful if your heart device sets off a metal detector or a security system.

Yes. Using a microwave won’t affect your ICD.

Don’t be all pins and needles about this one. Acupuncture is no problem, as long as it’s not acupuncture with an electrical stimulus. Electrical stimulus could be detected by your ICD, potentially resulting in an inappropriate shock.

Yes. Gas powered snow blowers can be used. It is recommended that you keep at least 12 inches between the running motor and the ICD.

Yes, you can. But keep it at least a foot away from your chest, which you’d probably do anyway.

Yes, you can stay toasty under your electric blanket without harming your ICD.