New study on iPod interference in pacemakersMay 14, 2007
Seventeen year old Michigan high school student Jay Thaker has presented a paper on iPod and pacemaker interference to the 2007 annual meeting of the Heart Rhythm Society in Denver, Colorado. The study concluded that iPods caused various types of interference in pacemakers in 50 percent of the patients tested.
The population tested in Thaker’s study had a mean age of 76.1 (plus or minus 8.6 years), which is admittedly not the prime demographic for iPods and other MP3 players. However, the results of the study give some indication of the kinds of issues that will arise as those currently in their 40s and 50s start to develop their own personal relationships with cardiologists.
Thaker, the son of an electrophysiologist and a rheumatologist, worked with several doctors from Michigan State University and the University of Michigan to test his theory of interference. Four different iPods – a third-generation MP3 player, a video iPod, a photo iPod, and a Nano – were held 2 inches above the chests of 83 patients with pacemakers. Each iPod was held there for five to ten seconds while a technician monitored electrocardiogram and pacemaker telemetry equipment.
The study revealed that three different types of interference can occur between an iPod and a pacemaker. Two types, oversensing (spurious sensing of atrial/ventricular events) and telemetry interference, were the most persistent and were measured in more than 50 percent of the patients. The third, most serious type of interference – pacemaker inhibition, or a failure to pace the heart when pacing was expected – occurred in just 1 patient.
Ironically, iPods are becoming a valuable tool in the training of new cardiologists. At the University of Michigan, in fact, Dr. Richard M. Judge has developed a podcast called “Electrocardiogram of the Week,” which third-year medical students can store on their iPods to practice reading and interpreting electrocardiograms.
Over at Temple University School of Medicine and Hospital, Dr. Michael Barrett, a clinical associate professor of medicine and cardiologist, has recorded several heartbeats with irregularities and stored them as MP3s.
Medical students can download the recordings to their iPods and use them to practice “cardiac auscultation,” or listening to the heart through a stethoscope. Dr. Barrett has found that when physicians and students practice first with the recordings, their ability to identify specific heart murmurs is twice as good.
Dr. Barrett is working with the American College of Cardiology to make the heart recordings available online and on CD, so physicians could listen to them during their commutes to and from work.
Clinically relevant or not, the iPod study’s findings found their way around the world in one form or another. How serious they seemed to be, however, depended on where one read them.