Effects of Electric Motors on St. Jude Medical Implantable Cardiac Rhythm Devices
An electric motor is a type of machine that converts electrical energy into mechanical energy. Electric motors operate through interacting magnetic fields and current-carrying conductors to generate force. The reverse process, producing electrical energy from mechanical energy, is accomplished by an alternator, generator, or dynamo. Electric motors may be powered by direct current (e.g., a battery powered portable device or motor vehicle), or by alternating current from a central electrical distribution grid.
At this time we have no reports of large-scale electrical motors or portable generators affecting our pacemakers or implantable cardioverter defibrillators (ICDs). However, this does not mean there is a total absence of effects related to electric motors. Extraneous radiated noise from large-scale electrical motors will not damage or reprogram a pacemaker or ICD. If large-scale electrical motors do affect a pacemaker or ICD, inhibition, reversion to asynchronous pacing, or inappropriate therapy may potentially occur. Some patients can tolerate reversion to asynchronous pacing or some inhibition of their pacemaker or ICD. Any problems caused by radiated interference will end when the electrical interference ends or the patient leaves the immediate area.
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.
|Inhibition of pacing or ATP/HV therapy
The risk of working with electrical motors and portable generators may be reduced to an acceptable level by observing proper techniques. Working on the motors with the power “OFF” will avoid electrical interference.
Large scale motors seen in the industrial environment may have a greater likelihood of interference. In power generating plants large motors are typically grounded and shielded which minimizes the radiation of electrical noise. If documentation is needed for a patient’s work environment, the physician can prescribe a Holter monitor, which records an ECG in the work environment. The physician can also program the pacemaker or ICD to bipolar modes of operation and reduce the sensitivity levels. These clinical suggestions can mitigate the potential effects of EMI.
If you have any questions on this topic, please contact St. Jude Medical Technical Services at 800-722-3774.
Effects of Electric Motors on St. Jude Medical Implantable Cardiac Rhythm Devices (21.1kb)