Coronary calcium scan

(heart scan / calcium score)

A coronary calcium scan, also referred to as a coronary artery calcium score (CAC), takes pictures of your heart using an X-ray technology called computerized tomography (CT). This imaging technology allows your doctor to detect and measure calcium-containing plaque in your arteries before it causes symptoms, leading to effective preventive treatments.

Detecting coronary artery disease early

Coronary artery disease is the leading cause of death in the United States. It’s caused by a buildup of plaque in your coronary arteries. This plaque buildup limits blood flow to your heart. Arterial plaque can also break apart, which can lead to dangerous clotting.

A coronary calcium scan, or coronary artery calcium score (CAC), identifies the amount of calcified plaque you might have. This helps your doctor accurately diagnose – and effectively treat – coronary artery disease before you experience any signs and symptoms.

Helping determine medication or lifestyle changes

There are numerous reasons why a calcium scoring test might be performed, each representing a unique patient journey. This test can be very helpful if you have a strong family history of heart disease. The test gives your doctor a better understanding of your long-term cardiac risk.

Depending on your test results, your doctor may suggest medication or lifestyle changes to reduce the risk of heart attack and prevent coronary disease progression.

How the test is done

Coronary artery calcium scoring is a very simple, minimally invasive procedure.

In order to make your scan go as smoothly as possible, here are several things you can do/need to know:

  • Don’t wear jewelry.
  • Wear loose, comfortable clothes.
  • Take your regular medications the day of the procedure.
  • There is no need for you to fast prior to the test.

Before the scan begins, a technician will place sensors called electrodes on your chest to track your heart rhythm during the exam.

The entire process typically takes 10 to 15 minutes. After the scan, you can drive yourself home and continue your daily activities. The scan will be read by a physician with results typically available within 48 hours.

Benefits and risks of the calcium score test

Multiple benefits

There are several benefits of a coronary calcium scan:

  • Although simple, it’s one of the most advanced methods available to determine early-stage heart disease or risk of a future heart attack.
  • It’s a convenient, noninvasive way of evaluating your coronary arteries.
  • The test is fast and painless.
  • No IV or injections are required.

Very few risks

There are very few risks associated with a coronary calcium scan.

The scan uses X-ray technology which entails some radiation exposure. The amount of radiation is considered low, about half the amount of radiation you’re naturally exposed to in a year.

Because of the exposure to radiation, pregnant women (or those who could be pregnant) should not pursue this test.

Lady and man riding bikes

Who should – and shouldn't – get a coronary calcium scan

Please consider getting a coronary calcium scan if you are 40 to 75 years old, not on a cholesterol-lowering medication, and there is uncertainty about whether you need to take a cholesterol-lowering medication like a statin.

The results of the CAC will help you and your doctor determine if a cholesterol-lowering medication would help reduce your risk of coronary artery disease.

If the CAC score is “0” you may not need the medication.

Generally, a coronary calcium scan is not recommended if you are:

  • Younger than 40. Most younger people don’t develop calcified plaque detectable by CT.
  • Someone who already is at a high risk. A calcium scan probably won’t provide any additional useful information to guide treatment.
  • Someone who already has symptoms or a diagnosis of heart disease. A calcium scan often won’t help doctors better understand the disease’s progression or associated risks. A calcium scan is not a good test if you have active symptoms.

Frequently asked questions (and answers)

Coronary calcium scores are very accurate. Unlike some other imaging tests, the results are unlikely to be either falsely negative or falsely positive.

Calcium scores directly visualize plaque buildup in the coronary arteries years before the plaque buildup can be detectable on other tests such as stress testing.

The cost for the test is $150.

In general, health insurance does not cover coronary calcium scoring. Patients will typically have to pay out-of-pocket for the test.

Since a calcium scan is designed to be used as a screening test, it’s not useful if you already have a stent, bypass, or known coronary artery disease.

Depending on your score, your health care provider will provide additional instructions for next steps, including treatment options if necessary.

Before you pursue a calcium scan, your doctor will estimate how likely you are to get heart disease based on certain risk factors. These include:

  • Your age.
  • Your blood pressure.
  • Your cholesterol level.
  • Your family history.
  • Your gender.
  • Whether you smoke.

Your doctor will determine if a coronary calcium scan is the right test for you based on these risk factors.

People who are very low risk are unlikely to have calcium score findings that lead to treatment.

People who are very high risk may need treatment for coronary artery disease regardless, and may need more complex coronary artery testing.

Knowing your CAC score can affect your everyday life by inspiring changes in your lifestyle. As always, consult your doctor for specific recommendations.

MedlinePlus: National Library of Medicine. Heart CT scan –

Pubmed: National Library of Medicine. Coronary Artery Calcium Scoring: Is It Time for a Change in Methodology? –