Scientists are testing a new implantable medical device designed to warn patients of impending heart attack.
The AngelMed Guardian aims to help many of the 300,000 U.S. heart attack patients who die each year before seeking medical attention – some of whom may not be aware of the warning signs, according to the device’s developers.
In an article cleverly entitled “This is your heart speaking. Call 911,” published in the journal Ergonomics in Design, Mary Carol Day and Christopher Young said the new device alerts users about a potential heart attack through a combination of vibrations, audible tones, and visual warnings.
The Guardian, which is currently undergoing clinical trials, is modeled after vibrating alarms that are sometimes used to warn medical personnel in operating rooms or ICUs of an emergency.
"A vibrotactile alarm provided by the implanted device has two major advantages," said Day. "First, the implanted device can't be left behind like a portable device. Second, a vibrotactile alarm from the implanted device is more likely to be felt than an auditory alarm is to be heard because, for example, the patient may be wearing heavy clothing, has hearing loss, or is in a noisy environment."
The Guardian is equipped with an alarm that triggers a patient to call 911 when he or she may be having a heart attack. A second, lower-priority warning indicates that a condition has been detected that requires a doctor visit within 48 hours. The device is similar in size to a pacemaker and is placed in the upper left chest. It comes with an external device, similar to a pager that emits an alarm and flashes a red or yellow warning light.
In tests of the device's design and user-friendliness, a group of seniors could tell the difference between the low-priority and high-priority vibration patterns and respond appropriately. They also reported that they liked the vibrating alarms and the redundancy of the auditory, visual, and vibrotactile warnings.
"If the Guardian is approved for sale by the FDA," Day said, "it might be extended in ways that will change the way the patient interacts with the system as a whole. This would require more research and simulated-use studies to refine and validate the new interactions between the patient and the system."