Coronary Calcium Scan

A computed tomography (CT) scan used to detect the buildup of calcium in plaque on the walls of the coronary arteries. The results of the test help to determine a person’s level of heart disease risk.

The coronary arteries are the blood vessels that supply blood to the heart. When they become narrowed or blocked from the buildup of plaque, the result is coronary artery disease, the leading cause of heart attacks. The plaque is composed of fat, cholesterol, and calcium, and the coronary calcium scan is designed to detect and quantify this calcium. Scans showing no calcification suggest a low risk of heart attack, while high calcium scoring signifies more plaque in the arteries and a higher risk of heart attack.


Coronary calcium scans aren’t recommended for everyone. For example, they aren’t recommended for people with either low or high risk of heart attack because they won’t tell the doctors or the people getting tested anything they don’t already know. The American Heart Association and the American College of Cardiology recommend coronary calcium scans for adults at intermediate risk for heart disease–namely, those believed to have a 10% to 20% risk of heart attack or cardiac death in the next 10 years.

A calcium score of 0 shows that the person has less than a 5% chance of developing heart disease. A score of 1—10 indicates less than a 10% risk of developing heart disease, and a score of 11—100 means that risk is less that 20%. A scan of 101—400 shows that the person has heart disease and a moderate-to-high risk of having a heart attack. A score of over 400 indicates a large amount of plaque and a 90% chance that the plaque is blocking one of the coronary arteries.

If calcium scanning shows that you’re at high risk for heart disease, talk to your doctor about how to protect your heart. Recommendations may include certain types of dietary changes, quitting smoking, and getting more exercise.