Share this on:Copied!

Heart disease is the leading cause of death in the United States, so prevention and early detection are key. One potentially beneficial screening is a calcium test for your heart.

A coronary artery calcium (CAC) test can show evidence of coronary artery disease — even if you don’t have symptoms. The results can help show your future risk of cardiovascular problems like heart attack and stroke.

When combined with other screenings, calcium scoring can help your doctor decide if you need further treatment or a cardiologist visit. It’s a tool that can benefit your heart health and help you prevent a heart attack or stroke.

Learn more about calcium score tests and what calcium scores mean.

What Is a Calcium Score Test?

A calcium scoring test is also known as a calcium scoring computed tomography (CT) scan. It’s a noninvasive, painless test that uses CT technology to take pictures of your heart.

The test can detect calcium in your arteries, which is a sign of plaque buildup (atherosclerosis). Plaque can cause narrowed or blocked arteries, potentially leading to a heart attack or stroke.

For a calcium scoring test, you’ll put on a hospital gown, remove metal objects, and lie flat on a table connected to a CT machine. When the test is underway, the CT machine will take images of your heart. You’ll also get connected to an electrocardiogram (EKG) that measures your heart’s electrical activity during the test.

The entire calcium scoring test lasts around 30 minutes.

Your doctor can determine whether and how much calcium you have in your arteries based on your images. This helps them calculate your calcium score.

What Is a Calcium Score?

A calcium score measures the presence and amount of calcium in your coronary arteries. The calcium is evidence of plaque buildup in your arteries.

You can measure the calcium score as an absolute number, also known as an Agatston score. The higher the score, the more at risk you are for heart attack and stroke in the next few years. Each range of score indicates the following:

• A score of zero: There’s no apparent evidence of coronary artery disease. You’re at low risk for heart attack and stroke.
• A score between 1 and 10: There’s minimal evidence of coronary artery disease. You’re at low risk for heart attack and stroke.
• A score between 11 and 100: There’s mild evidence of coronary artery disease. You’re at mild risk of heart attack and stroke.
• A score between 101 and 400: There’s moderate evidence of coronary artery disease. You’re at moderate risk of heart attack and stroke.
• A score of 401 and higher: There’s high evidence of coronary artery disease. You’re at high risk of heart attack and stroke.

You can also measure a calcium score as a percentile that measures people against others of the same age, race, and sex. Your absolute score and percentile combined can better indicate your overall risk.

What Does a Calcium Score Indicate?

Along with other screenings, a calcium score can help indicate your current risk of heart disease. It can also help predict your risk of cardiovascular events like heart attack and stroke.

Depending on your calcium score and other risk factors, your doctor may prescribe medication for your heart. They may also refer you to a cardiologist for further treatment or recommend lifestyle changes.

What Is a Good Calcium Score?

A normal calcium score is zero. That means you have no apparent evidence of coronary artery disease.

A score of zero doesn’t necessarily mean that you don’t have coronary artery disease. You can still have plaque buildup without calcium deposits.

It also doesn’t guarantee that you’ll never have a heart attack or stroke. But it means you face a lower risk than people whose score isn’t zero.

According to the American College of Cardiology, a score of zero is a strong indicator that you won’t have a cardiovascular event in the next 10 to 15 years.

What Is a High Calcium Score?

Any calcium score above zero indicates that you have at least some evidence of heart disease. The higher the score, the more evidence there is — and the more risk you face of heart attack or stroke. A score above 400 means you’re at high risk of a heart attack or stroke.

Calcium scores can also climb into the thousands. According to a 2021 study in Radiology Cardiothoracic Imaging, a calcium score above 1,000 is indicative of a “distinct very high-risk group.” People with a score over 1,000 face an even higher risk of heart attack and stroke than any other group.

Does a High Calcium Score Mean I Have a Blockage?

The higher your calcium score, the greater the likelihood that you have at least some level of blockage in your arteries. But a calcium scoring test alone can’t show the level of blockage in your arteries. For that, you’d need a different test, such as a coronary CT angiogram.

Who’s Eligible for a Calcium Scoring Test?

Generally, doctors recommend calcium scoring tests for men over 40 and women over 50 who are at average risk for heart disease. You may want to take a test sooner if you’re at high risk of heart disease or have a family history.

If you’re pregnant, your doctor may recommend you wait until giving birth before you get a calcium test. Also, you shouldn’t get a calcium scoring test if you already have a diagnosis of coronary artery disease.

If you’re wondering if you should get a calcium scoring test, talk to your doctor.

Should I Get a Calcium Scoring Test?

A calcium scoring test is one of many cardiovascular screenings that can help determine your risk for heart disease, heart attack, and stroke. It can help detect coronary artery disease even if you don’t have symptoms.

According to Radiology Cardiothoracic Imaging, about half of the people who die from cardiovascular disease have no prior symptoms or diagnoses. That makes any test that can help show your risk of heart disease important.

A calcium scoring test can’t detect all forms of heart disease, but it still has benefits. If you think you could benefit from a calcium scoring test, talk to your doctor about getting a referral. You’ll need a doctor’s referral for the test.

UPMC Heart and Vascular Institute is a national leader in the prevention, diagnosis, and treatment of a wide range of cardiovascular diseases. For more information, visit our website.

Editor's Note: This article was originally published on July 2, 2024, and was last reviewed on March 21, 2025.