Following reports of a study suggesting that personal music players, such as iPods, can have a temporary effect on the operation of implantable pacemakers, the MHRA has advised that patients with pacemakers or defibrillators can use personal electronic equipment with negligible risk, providing they are not placed directly over the implant, for example in shirt pockets etc.

The MHRA is aware of results of a small study in the USA that indicated that personal music players, such as iPods, can have a temporary effect on the operation of implantable pacemakers if they are in very close proximity. Details of this study are available from the Heart Rhythm Society, USA (www.hrsonline).

Details of the study were first made public at the annual Heart Rhythm Society meeting in Denver USA during the week ending 12 May 2007. The researchers studied the effect of placing an iPod over the pacemaker in 83 patients and switching it on and off for 5 - 10 seconds. They recorded transient increases in heart rate in one in five patients and a temporary cessation of pacing support in one patient. The effects seen were transitory and there was no permanent change in pacemaker therapy or symptoms in the patients.

The MHRA is not aware of any reports in the UK of interference problems between MP3 players and pacemakers. There is no evidence that personal music players such as iPods and other brands of disk-based and solid state MP3 players can permanently affect the operation of implanted pacemakers or defibrillators.

The MHRA advises that patients with pacemakers or defibrillators can use personal electronic equipment such as iPods and other brands of disk-based or solid state MP3 players with negligible risk, providing they are not placed directly over the implant. Maintaining a separation distance of at least 15cm (6 inches) between the two avoids interference effects. The same advice holds true for mobile phones and palm/pocket PCs etc.

The MHRA has previously issued advice about interference to pacemakers and defibrillators from mobile phones, electronic article surveillance systems (EAS) and magnets. Summaries of this advice are available in the Publications and Safety Warnings section of MHRA's website (www.mhra). We are continuing to investigate the possibility of problems arising with implantable electronic devices as a result of interference form other equipment and have asked manufacturers of implantable pacemakers and defibrillators to advise of any circumstances where a risk to patient health is associated with electromagnetic interference. www.mhra