Coronary calcium score can provide important information on your risk of having a heart attack

Heart disease is the No. 1 killer of Americans. In the United States, it's estimated that someone has a heart attack every 40 seconds.

These are scary statistics, but there's one test that can give you more information on your risk of having a heart attack.

From blood pressure and cholesterol checks to numerous cancer screenings, as we age the roster of recommended medical tests keep getting longer and longer. And now doctors say there's one more to add to the list.

"The coronary calcium score is actually a CAT scan. It takes two minutes to acquire the images and very little radiation is involved," said Dr. Pamela Rama, a preventative cardiologist.

The CAT scan is then used to create a scale from zero to 400.

"And what it does is it looks at your coronary arteries to see if there's any calcium in your coronary arteries. And if we find calcium, it's equivalent to having coronary artery disease," Dr. Rama explained.

A score of zero means there's no plaque present. The higher the score, the more plaque present. But Dr. Rama says even a low score doesn't mean you're in the clear.

MORE: How stress can lead to a heart attack

The head-heart connection is a lot stronger than you might think. While we all know how stress can be a contributing factor to heart disease, you may not realize that stress alone can stop blood flow to the heart.

"Even a score of 1 means that you have coronary artery disease. What draws the calcium into the coronary arteries is cholesterol plaque. So, for me, it's the best predictor of cardiac events that we have so far, " she said.

Not only can it determine your risk, but Dr. Rama also uses it to decide if her patients need lifestyle changes and medical interventions. For some, the test offers reassurance.

"When I have patients who have high cholesterol levels and their coronary calcium score is zero, I actually stop their statin therapy and they love it," she said.

The only people who don't need the test would be anyone who has already been diagnosed with coronary artery disease. It runs from $100 to $400, depending on insurance coverage.

While Dr. Rama says it's not a test that needs to be repeated every year, she does suggest repeating it in five years if you score zero. It's information even the healthiest of people should take into account.

Experts say knowing your calcium score can also play a role in deciding whether or not to start statin therapy.