Coronary Calcium Score

What is it?

It is a number reflecting the quantity and distribution of calcium in the arteries to your heart (coronary arteries). Calcium is a bit of a Jekyll-and-Hyde mineral. It is good, in that it is required for proper function of multiple body systems, such as bone, muscle and nerve. But calcium can be bad, when it accumulates in places like the kidneys (kidney stones) and in arterial plaque, especially in the heart and neck (carotid) arteries.

What is Plaque?

Atherosclerosis, aka “hardening of the arteries,” is the deposition of fat, cholesterol and other substances in the walls of arteries. These plaques can begin as early as age 20. Eventually, they enlarge and narrow the artery, causing reduced blood flow and subsequent damage to heart muscle. Calcium is often deposited in plaques, so it is an indicator of overall plaque burden.

What are the Risk Factors for Heart Attack?

Risk factors for coronary heart disease are age, gender, cigarette smoking, diabetes, high blood cholesterol level, high blood pressure and family history of heart attack and stroke. These factors are most often used to predict the likelihood of a future heart attack. Coronary artery calcium has also been identified as another factor. Calcium score correlates well (but not perfectly) with the amount of plaque and consequently, the risk of a future heart attack. The more calcium in your arteries, the more likely you are to have a future event.

How Do Doctors Determine My Calcium Score?

Coronary artery calcium can be detected and quantified using a specialized CAT scan (CT) of the heart. The scan is relatively simple and quick for the patient. No “dye” needs to be injected, the amount of radiation is low, compared to other types of CAT scans, and you only hold your breath for about 10 seconds or so. The test is also less expensive than most other types of CT scans. The score ranges from zero to well over 1,000. The higher your calcium score, the higher your risk.

Who can Benefit?

The test is not for everyone. If your risk for heart attack is low (a non-smoker less than 55 years old with normal blood pressure and cholesterol and no family history of heart disease, for example), the scan probably won’t yield significant additional information. If your risk is high (over age 65 with high cholesterol, diabetes and high blood pressure, for example), the scan won’t add much because you have (or should have!) already made significant changes in your life style and started appropriate medication. The score is best for patients with “intermediate” risk (55–65 age range with borderline cholesterol or diabetes, or a smoker, for example). A score from 0–100 indicates lower risk, so preventive treatments may not be necessary. A score over 400 indicates higher risk, so your doctor may recommend additional measures, like medications to lower cholesterol, in addition to dietary changes, smoking cessation and institution of an exercise program.

By Geoff Rieser, MD, PhD, Staff Radiologist with Triad Radiological Associates