Every 43 seconds, someone in the United States has a heart attack.

It's not the only startling statistic from the CDC – 735,000 Americans have a heart attack every year.

If someone had a heart attack near you, would you know what to do? Your first, most important option is to perform CPR. But you may also have access to an automated external defibrillator – or AED.

AEDs scan a person who is having a heart attack and, if needed, deliver an electric shock to the person's cardiovascular system.

AEDs can be found in some churches, public buildings and workplaces, and more and more places are getting them every day.

As AEDs become more common, the potential for saving lives grows. According to the American Red Cross, improved training and access to AEDs could save 50,000 lives each year.

How do you use an AED? J.T. Smith, MSN, chest pain center coordinator for Spartanburg Medical Center, describes how in this video. Also, there's an informational infographic, below. Familiarize yourself with these facts, and you'll be able to confidently help during a cardiac emergency.

You can be the one to save a life.

No one is ready for a heart attack, but you can be ready to help. If someone has collapsed with chest pain, follow these 5 steps.

1. “Hey, hey, are you OK?”
2. Tell someone to call 911 and find an AED
3. Begin chest compressions immediately
4. Turn on the AED and follow the step-by-step audio instructions
5. Do not leave the person alone; continue chest compressions until help arrives

What will the AED tell me to do?

• Place the pads on the person's chest and then plug in the connector
• Do not touch the person while the AED is taking a reading
• After the AED listens to their heart, it will tell you whether a shock is needed
• Tell others to stand clear of the person
• Deliver the shock by pushing the button
• Continue chest compressions until help arrives