Coronary Calcium Scan Test
Overview
A coronary calcium scan is a type of CT test that checks for calcium buildup in the coronary arteries. This buildup, known as calcification, can point to plaque forming in the blood vessels that supply the heart.
Plaque and calcification strongly indicate coronary artery disease (CAD) or coronary heart disease. When calcium blocks the arteries, it can limit blood flow to the heart. This process is also called atherosclerosis.
Doctors use results from this scan to look for early signs of heart disease—even if a person has no symptoms. This test helps find soft or hard plaque and assists with planning CAD treatments. Other names for this test include:
- Coronary artery calcium test
- Heart CT calcium scan
- Coronary calcium CT scan
Reasons for Testing
Coronary calcium scoring detects calcium in the arteries that carry blood to the heart. Calcium buildup makes up part of plaque, which can lower blood flow and increase the chance of a heart attack.
Doctors recommend a coronary calcium scan for certain people, such as those with a strong family history of heart disease, people with high cholesterol, or those with diabetes.
They especially use it when traditional risk tools, such as the pooled cohort equation, do not give a clear answer about risk. People who have chest pain but unclear test results, or who fall into an intermediate risk group, may also benefit from this test.
Situations When a Coronary Calcium Scan Is Considered
- Family history of early heart disease.
- High cholesterol or diabetes.
- Traditional risk factors but unclear overall risk.
- Intermediate or uncertain risk for a heart attack.
- Unclear results from stress testing.
The scan provides a score that measures the amount of calcium seen. A higher calcium score signals a higher risk for heart problems. However, this test is not for everyone. People who have already had a heart attack, stent, or bypass surgery do not need this test because other tests have already shown artery health.
Possible Dangers
A coronary calcium scan uses radiation exposure because it uses an X-ray to capture images. While the level of radiation from this test is usually low and safe for most people, repeated scans can add to a person’s lifetime exposure.
Some centers offer this scan without a referral, but the test is not always covered by insurance. Alternatives like blood pressure readings and basic blood tests may give useful information about heart health, sometimes at a lower cost.
How You Prepare
Patients should avoid smoking and caffeine for several hours before the test. Health care staff may give more specific directions. When arriving, patients usually need to wear a provided medical gown. Remove all jewelry from around the neck or chest to help ensure clear test results.
What You Can Expect
What Happens While the Scan Takes Place
Before starting the heart scan, a healthcare professional places small electrode patches on the patient’s chest and sometimes on the arms or legs. These connect to an electrocardiograph (EKG) to track the heart’s rhythm. The scan takes place in a computed tomography (CT) scanner.
The patient lies on a moving table that gently slides into a large, tube-shaped machine, with their head staying outside. The room may feel cool, and sometimes staff give medicine to slow the heartbeat, which helps get clearer pictures.
Staff can also offer relaxation medication if needed. Patients must stay still and may need to hold their breath briefly while images are captured. The staff can see and speak with the patient during the entire test. The scan usually finishes in 10 to 15 minutes.
What Happens After the Scan Is Finished
The computed tomography test causes no pain or lasting effect. Once the heart scan is complete, most people can get up right away and leave. No recovery period is needed unless a doctor gives special instructions. Patients can resume regular activities, such as driving, immediately.
Test Outcomes
Talking About Your Scan Results With Your Medical Team
After the coronary calcium scan, a person receives a calcium score known as the Agatston score. This score shows how much calcified plaque is inside the arteries of the heart. A higher score means more plaque in the arteries, which can indicate a higher risk for heart problems.
What Do Calcium Scores Mean
| Agatston Score Range | What It Means | Heart Risk Level |
|---|---|---|
| 0 | No calcium is found | Low risk |
| 1–99 | Small amounts of calcified plaque | Mild risk |
| 100–299 | Moderate plaque is present | Higher, moderate risk |
| 300 and above | Large amount of plaque, more extensive disease | High risk |
Some reports also show a percentile rank. This score compares the amount of calcium found in the arteries to that found in other people of the same age and gender. For example, a calcium score above the 75th percentile often means a much greater risk for heart attacks compared to most people in that group.
Next Steps After Getting Results
When discussing CAC results, the doctor may recommend:
- Continuing the current care plan
- Changing or starting medication
- Adjusting diet and exercise
- Setting new weight goals
- Extra health tests
- More regular follow-ups
If the scan finds calcium in the arteries, patients usually do not need to repeat the test. The results should always be reviewed along with other health information. It is not enough to use the calcium scoring alone to make decisions about heart health or treatment. The healthcare team will help explain what the Agatston score and calcium scores mean for a person’s unique situation.
