It's a stark statistic. More than one million people in the United States suffer a heart attack every year and more than 30 percent of them die before they can receive medical attention.
One big reason for that, doctors say, is that most victims are unaware that they are suffering a life-threatening attack until it is too late. The average time from the onset of symptoms to when a victim arrives at a hospital is about three hours.
What if your heart had an alarm that could sound when it was about to go into arrest? That may not be so far-fetched.
Clinical trials are now underway for an implantable device called the AngelMed Guardian. It is designed to alert users about a potential heart attack through a combination of vibrations, audible tones, and visual warnings.
The concept stemmed from the hospital environment itself. Vibrotactile, or vibrating alarms are sometimes used to warn medical personnel in operating rooms or ICUs of an emergency. Now, research is focusing on their use as a means to warn patients that something in their body is going wrong.
Auditory alarms are provided with selected implantable heart defibrillators, but research indicates that some patients - particularly the elderly - are unable to hear the alarms.
“A vibrotactile alarm provided by the implanted device has two major advantages,” said Mary Carol Day, a researcher who has studied the device. “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 device offers two levels of alarm urgency: a high-priority alarm indicates that the patient may be having a heart attack and should call 911, and a low-priority alarms indicates that a condition has been detected that requires a doctor visit within 48 hours.
The alarms are provided by an implanted medical device, similar in size to a pacemaker, that is placed in the upper left chest, plus an external device, similar to a pager, that emits an auditory alarm and flashes a red or yellow warning light.
The device is not yet available for consumers, but might be in the future, depending on the results of the clinical trials.
“If the Guardian is approved for sale by the FDA, it might be extended in ways that will change the way the patient interacts with the system as a whole,” Day said. “This would require more research and simulated-use studies to refine and validate the new interactions between the patient and the system.”