Electromagnetic Compatibility

Patient Services Electromagnetic Compatibility Guide

For Implantable Cardiac Devices


Activities and Intimacy

The goal is for you to lead a normal life as soon as possible. Here are suggested precautions to follow during your recovery period.

Your physician will provide you with specific directions based on your current medical condition and history.

Q: What activities can I resume?
A: Generally, your device will not keep you from most activities and hobbies (e.g., bowling, golfing, playing tennis, gardening, fishing, etc.).

Q: Will I be able to return to work?
A: Most patients are able to return to work after device implant. You and your doctor will make this decision. The timing will depend on many things, including the type of work you do.

Q: Will my ICD deliver a shock during intimacy or daily activities? 
A: It is rare. Your ICD is programmed to allow your heart to normally rise without treatment shocks being delivered. Your device should only deliver a shock when your heart rate meets the specific criteria programmed by your heart doctor. If you receive a shock during intimacy or other activities, contact your physician. Your doctor will then determine the cause of the shock and may also make adjustments in the programming of your heart device.

Q: Will I be able to resume sexual activity?
A: Intimacy is a normal part of life. We understand patients resume sexual activity when they feel comfortable. However, if you have a question, it may be helpful to have a conversation with your doctor.
If in doubt about an activity, always discuss with your doctor or nurse.


MRIs

Q: Are heart devices MR-compatible?
A: Currently, most heart devices are not considered safe in an MRI environment because the MRI could change the settings and/or temporarily affect the normal operation of the heart device. Medtronic has CRT-D, ICD, and pacing systems which are FDA-approved for use in the MRI environment. These systems have a unique design, developed so that under specific conditions, patients may safely undergo MRI scans.

Talk to your doctor about the pacemaker, ICD, and CRT options available to you, and determine if your current or future cardiac system allows you safe access to an MRI scan.

For more information, please visit www.mrisurescan.com or www.mypacemaker.com

Q: What if my device is not FDA-approved for use in the MRI environment? 
A: Medtronic does not recommend the use of an MRI scan if your device is not FDA-approved for use in the MRI environment. Your physician should discuss all potential benefits and risks with you.

Q: What if my doctor strongly recommends an MRI scan?
A: 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. This card will advise them to contact your attending heart doctor. If needed, your doctor can seek more information from a Medtronic representative.

Q: If I had an MRI scan, did this affect my heart device? 
A: Your doctor can determine if there is an effect on your heart device. If you did not see your doctor after an MRI scan, contact your doctor.


Anti-Theft Detectors and Airport Security Systems

Q: Can I go through store anti-theft detectors? 
A: 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.

Q: Can I go through security systems such as those found in airports and courthouses? 
A: Given the short duration of security screening, it is unlikely that your Medtronic heart device will be affected by metal detectors (walk-through archways and hand-held wan\ds) or full-body imaging scanners (also called millimeter wave scanners and 3D imaging scanners) such as those found in airports, courthouses, and jails. 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 alternative screening, and then follow the instructions of the security personnel.


Household Magnets

Q: Do magnets affect pacemakers and implantable defibrillators?
A: 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.


Welding and Chainsaws

Q: I read in my patient manual that I should avoid welding. Why? 
A: 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.

Q: What if I may need to use a welder? 
A: 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 (60 centimeter) 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.

Q: I read in my patient manual that I should avoid using a chainsaw. Why?
A: The electromagnetic energy generated by a chainsaw is similar to other electric and gasoline 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.

Q: What if I may need to use a chainsaw? 
A: You may need to use a chainsaw from time to time. Follow the safety precautions below to minimize the risk of interfering with your heart device while using a chainsaw.

Chainsaw Safety Precautions

  • Maintain a 6-inch distance between the motor of an electric chainsaw and your heart device. Also, be sure the equipment is properly grounded.
  • Maintain a 12-inch distance between the components of the ignition system of a gaspowered chainsaw and your heart device. Also, it is better to use one that is built with the spark plug located away from the hand grips.
  • 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