October 23rd, 2015 | The Blog
According to a recent study, there is good data to support the recommendation that smartphones should be kept a safe distance from implanted cardiac devices. There is a rare chance that signal interference can happen when they are in close proximity. The devices affected include the 2.9 million pacemakers implanted between 1993 and 2009 and implanted defibrillators.
The study was done using the Samsung Galaxy 3, Nokia Lumia and HTC One XL smartphones. Patients with implanted cardiac devices placed a smartphone directly on the skin over the implanted device to document the effect.
Patients with implanted cardiac devices were connected to a radio communication tester, which works like a mobile network station. Then, using the maximum transmission power and 50 Hz frequency, which are known to cause interference, the implanted device function was observed and recorded. At the same time, the patients were connected to an electrocardiogram machine to record their cardiac activity.
There were 3,400 tests conducted and only one implanted defibrillator misinterpreted the electromagnetic waves sent by the Nokia and the HTC smartphones. This confirmed that there is a potential for a problem, albeit a rare situation.
The Study Interpretation
In this day and age, most people have a smartphone of some sort. Patients with an implanted cardiac device can use a smartphone but should not place the phone directly over the cardiac device.
A pacemaker can misinterpret the electromagnetic interference (EMI) from smartphones. This can be potentially dangerous to the patient.
The most vulnerable times during a cellphone call are while the call is ringing and when it is connecting to the network. Actually talking on a cellphone was not a vulnerable time.
What Does the Information Mean for Daily Life?
A pause in the cardiac device function can cause a pacemaker dependent patient to experience syncope or faint. Another issue is that an implanted cardiac device can misinterpret smartphone interference as a life-threatening, abnormal heart rhythm called ventricular tachycardia. This malfunction causes the implanted device to deliver a very painful and alarming shock to the heart.
Here are some recommendations derived from the study for patients with implanted cardiac devices to follow:
There is no major concern for patients whose pacemakers are programmed in the usual configuration. The most concern about the interaction between smartphones and implanted cardiac devices is for those with pacemakers in the unipolar mode or with extremely sensitive settings for a variety of reasons.
It is always best to seek the advice of the specific cardiac healthcare professional that cares for the patient. The standard of care expectation is that each patient will be counseled at the time a cardiac device is implanted and at subsequent follow-up visits.