Effects of Therapeutic Magnets on St. Jude Medical Implantable Cardiac Rhythm Devices

Background

Therapeutic magnets are used to provide pain-relief, improve circulation, promote relaxation and enhance well-being. However, the FDA has yet to approve any static magnet for therapeutic use.

Potential effects

St. Jude Medical pacemakers and implantable cardioverter defibrillators (ICDs) have a magnetically activated reed switch/GMR/telemetry coil which can be affected by magnets. The minimum magnet flux density needed to close the reed switch and therefore affect the pacemaker or ICD is 5 gauss.

A summary of potential effects is provided in the table below and is based on device testing at St. Jude Medical, clinical experience and/or a review of the scientific literature.

Potential Effect Estimated Frequency
  Pacemakers ICDs
Asynchronous pacing/Inhibition of therapy Common Common

 

Recommendations

The gauss level of magnetic mattress pads or magnetic necklaces could range from 400-700 gauss and standard therapeutic magnets typically range from 200-2000 gauss. Therefore we recommend that individuals with pacemakers or ICDs do not use these items. Magnetic bracelets, shoe insoles, belts, knee braces and joint wraps should not affect the pacemaker or ICD, especially when worn below the waist.

If you have any questions on this topic, please contact St. Jude Medical Technical Services at 800-722-3774.

PDF Effects of Therapeutic Magnets on St. Jude Medical Implantable Cardiac Rhythm Devices (18.4kb)
Rev. 01/11