Stop What You’re Doing and Schedule This Heart Test

What if one little-known test could reveal your risk of heart disease better than any other?

Traditional tests of heart disease risk are like looking at your phone to check the weather. Based on reports from other services and some complex modeling, you can see if it’s likely to be raining outside.

A coronary artery calcium (CAC) scan is like walking outside to see if it’s raining or not. It’s a direct look at what’s happening.

Assessing your risk of heart disease with a coronary calcium scan is different from previous models of risk assessment, says Dr. Regis Fernandes, a cardiologist at Mayo Clinic specializing in preventive cardiology.

“The whole thing about the coronary calcium score is it’s a more personal test. We’re talking about personalized risk.”

And that’s a big change in how we talk about your risk of heart disease.

How Coronary Artery Calcium Scans Change the Game

In other types of tests, says Dr. Fernandes, looking at specific markers tells us about a person’s risk of having coronary artery disease, which can precede a heart attack or stroke.

“The risk of heart disease increases if you have diabetes, high blood pressure, high cholesterol, smoke, etc. But it doesn’t tell us [if you have the disease]—it’s just a risk.”

Coronary calcium scans are different. “Once you have this test, it’s not a risk,” says Dr. Fernandes. “This test is a standard that you do have the disease.”

A coronary calcium scan doesn’t tell you if you’re at risk of coronary artery disease—it tells you to what degree you already have it and how that might affect your chances of a heart attack or stroke in the future.

To understand how the test works, we need to understand coronary plaque buildup.

How Coronary Artery Calcification Happens

Coronary artery plaque is a buildup of fat and cholesterol in the arteries of your heart. This is called atherosclerosis. Plaques make arteries narrower, reducing blood flow in the heart.

This can cause problems on its own, like shortness of breath or chest pain. And, if one of those plaques ruptures, it can form a blood clot. That clot could cause a heart attack or a stroke.

Once plaque has been building up for about five years, according to the Cleveland Clinic, it can start to calcify, or accumulate calcium.

“The calcium stabilizes the plaques,” says Dr. Fernandes. Calcification is actually your body protecting itself . . . but the presence of that calcium can alert us to potentially dangerous plaques. It’s the smoke, while the plaque is the fire, explains Fernandes.

So what causes the buildup of plaque in the first place?

All the familiar risk factors for heart disease that you’re familiar with. High LDL cholesterol and triglycerides in your blood, high blood pressure, tobacco use, diabetes, obesity, genetics . . . if you’ve heard that something is bad for your heart, it’s probably because it contributes to atherosclerosis.

If the plaque buildup goes untreated, it will continue to grow. And, eventually, it’ll calcify. And that’s where the coronary artery calcium scan comes in.

What A Coronary Calcium Scan Can Tell You

A coronary artery calcium scan is a CT scan for your heart that tells doctors how much calcium buildup has occurred. 

“It takes literally 15 seconds to have you scanned with your clothes on,” says Dr. Fernandes. “You don’t need an IV with medications, contrast, nothing. You just lay down.”

CT scans use X-rays to get a look inside your body. It’s only a small amount of radiation—about the same amount as a mammogram, says Dr. Matthew J. Budoff, a professor of medicine at UCLA specializing in cardiac CT scanning.

The CT scan shows you how much calcium buildup you have in your coronary arteries. You’ll also receive a score that can be used to get an idea of your risk of future heart attacks.

What’s Your Calcium Score?

You might also hear this test called calcium scoring—you’ll receive a score at the end of the test telling you about your heart attack risk.

If your score is under 100, you have little calcium buildup and not much risk of a heart attack or other heart disease in the near future. If you’re in the 100 to 300 range, you have a moderate risk. If you’re over 300, your risk is high.

You might also receive a percentile score. These scores can be confusing—some people mistake them for a measure of blockage, but they actually compare you to other members of your gender and age group.

Be sure to talk to your doctor about your score and its interpretation. A cardiologist can take other factors into account when telling you whether you should start cholesterol-lowering treatment.

Who Should Get a Coronary Calcium Scan?

The coronary calcium scan sounds great—it’s an easy, non-invasive test that tells you about your heart disease risk. So should you run out and schedule one right now?

Maybe.

Dr. Budoff says that the test is especially important for people with risk factors like a family history of heart disease, diabetes, high cholesterol, high blood pressure, or a history of smoking. He also points out that heart disease is the number one cause of death in men and women in the United States, so it gets more important as we age.

Dr. Fernandes recommends the test for anyone testing in the “borderline” or “intermediate” categories of the Pooled Cohort Equation (PCE), a formula that you can fill out online with some of your basic health stats.

As with most diagnostic tests, if you’re not sure, you can ask your primary care physician to see if it’s warranted.

Will Insurance Cover a Coronary Calcium Scan?

Of course, there’s a question of cost. Some insurance plans will cover a calcium scoring test, but not all.

The American Heart Association reports that a coronary calcium test can range from $100 to $400. If your insurance covers the test, you could be looking at less.

But even at $400, getting a direct look at your heart disease risk is probably worth it. Especially if you have risk factors for coronary artery disease. Even if you don’t, being in your 50s or 60s might warrant a look at your heart.

Get Tested If You’re at Risk—And Keep Emphasizing Heart Health

If you have high blood pressure, a history of smoking, a family history of heart disease, or other risk factors, a coronary calcium scan can tell you a lot about the state of your heart.

Whether you decide to get tested or not, keep doing the things that are good for heart health. Focus on a balanced diet with plenty of vegetables and whole grains. Exercise regularly. Drink lots of water.

And, when your doctor recommends it or you’d like a little more insight into the state of your coronary arteries, schedule a CAC test.