By Hank Clever, MD, as published in the St. Peters Journal .

We hear a lot about cardiovascular health and the risk of heart attack and stroke. Yet more than 1,000 people die each day because their heart stops with no warning or prior sign of heart disease.

This is known as sudden cardiac arrest, and only one in 20 people survive it. Of the nearly 300,000 Americans who die from sudden cardiac arrest every year, the American Red Cross estimates that more than 50,000 could be saved by the use of automated external defibrillators (AEDs).

"Defibrillators work by shocking the heart to completely depolarize the heart," explains Dennis Glascock, DO, a physician on staff at SSM St. Joseph Health Center who specializes in cardiovascular disease and electrophysiology.

"If administered in a timely manner, this jolt of electricity helps the heart regain a regular rhythm. For every minute in cardiac arrest, the chance of survival drops by 10 percent, so this shock has to be delivered within 10 minutes - hopefully sooner."

In the past, the only people who could monitor heart rhythms and operate manual defibrillators were trained medical professionals. But computer chips within AEDs instantly monitor and analyze the heart's rhythm and the devices now use voice prompts that can instruct even minimally trained people to save a life.

After turning on the AED, the operator is instructed to apply the machine's two electrodes to the victim's chest. The machine then detects the victim's cardiac rhythms and, if necessary, instructs the operator to stand back and press a button to administer the electrical impulse.

Although using an AED is fairly simple, individuals must receive training to operate the machine. During Red Cross training sessions, individuals learn the "cardiac chain of survival": a quick call for medical care, cardiopulmonary resuscitation, early defibrillation, and advanced cardiac life support, if needed.

"AEDs are becoming more common in large corporations, shopping malls, sports facilities, schools and airports," Glascock says. "When an organization or facility obtains an AED, a medical director oversees its storage, use and appropriate personnel training. Most police officers, firefighters and emergency medical technicians are required to be AED trained, and Missouri requires all AED owners to register with local emergency medical services so that emergency communications and medical services personnel are aware of AED placements."

AEDs are becoming more common, but you can't just go out and buy one. If you're interested in an AED for an organization or business, Glascock suggests contacting the local branch of the American Heart Association or American Red Cross. Like many powerful lifesaving cures, AEDs are available by prescription only.