The question of whether hearing aids interfere with pacemakers arises from general concerns about electronic device interaction with implantable medical technology. A pacemaker is a small, implanted device designed to monitor the heart’s rhythm and deliver a timed electrical pulse to ensure proper heart function. Modern hearing aids, even those with wireless capabilities, present a very low risk of causing harmful interference with these cardiac devices. This minimal risk is primarily due to the low power output and the physical separation between the devices during normal use.
How Electronic Devices Can Affect Pacemakers
Pacemakers operate by sensing the heart’s natural electrical signals to determine when pacing is required. However, they are vulnerable to external energy sources known as Electromagnetic Interference (EMI). EMI occurs when an external electromagnetic field mimics the heart’s intrinsic electrical signal, confusing the pacemaker’s sensing circuitry.
If the EMI is strong enough, the pacemaker may misinterpret the external signal as a natural heartbeat. This can cause it to temporarily stop delivering necessary electrical pulses, a condition called inhibition. Alternatively, interference could cause the device to switch into a fixed-rate pacing mode, pacing at a set rate regardless of the heart’s actual rhythm.
While pacemakers are shielded to resist environmental EMI, intense or prolonged exposure to high-strength electromagnetic fields can still disrupt their function. Sources that generate strong magnetic fields, such as industrial equipment or certain medical procedures, pose the greatest risk.
Hearing Aid Technology and Interference Risk
The risk of interference from hearing aids is extremely low due to their minute power output and location on the body. Modern hearing aids use wireless technology, like Bluetooth, but their radiofrequency transmission power is minimal. This power is significantly lower than that emitted by many common electronic devices, such as mobile phones.
The physical distance between the hearing aid, which sits on or inside the ear, and the pacemaker, typically implanted in the chest, is usually sufficient to prevent any meaningful interaction. Furthermore, these devices must adhere to strict regulatory standards, such as those set by the Federal Communications Commission (FCC). This regulation limits the maximum radio frequency transmission power for devices worn close to the head, ensuring the electromagnetic field strength is nearly immeasurable at a distance from the head.
Assistive Listening Devices (ALDs)
A potential concern involves assistive listening devices (ALDs) that use a neck-loop antenna worn around the chest. This type of device uses a magnetic field to transmit audio directly to the hearing aid’s telecoil feature. Although the neck loop is closer to the pacemaker site, studies suggest that while the device may create electromagnetic interference on an external electrocardiogram (ECG) recording, the actual function of the implanted pacemaker is rarely affected. The cardiac device remains largely resistant to these low-level fields.
Safety Guidelines for Pacemaker Wearers
Pacemaker recipients should discuss the use of any new electronic device, including hearing aids and accessories, with their cardiologist or clinic. While hearing aids are generally safe, maintaining a small buffer distance offers caution, especially with wireless accessories. The general recommendation for most consumer electronics is to keep them at least six inches (about 15 centimeters) away from the pacemaker implant site.
This distance is relevant for any wireless accessory, such as a remote control or an assistive listening neck loop, carried in a shirt pocket or worn around the neck. If a person suspects interference is occurring, they may experience symptoms such as dizziness, lightheadedness, or a rapid or irregular heartbeat. In such a rare event, the recommended action is simply to move the source of interference away from the chest, allowing the pacemaker to return immediately to its normal function.