Coronary Artery Calcium Score Tests in Bangkok

The Coronary Calcium Scan is a type of CT scan that looks for calcium in the coronary arteries, the arteries that supply the heart itself with blood, and are, when occluded or narrowed, in causing angina, 'heart attacks', myocardial infactions. The calcium the scan is looking for is part of plaque, a waxy substance at first, that grows slowly and over time hardens and can become calcified. Simplified, the presence of calcium in the coronary arteries, indicates that something has been going on, that inflammation occurred, and that plaque is present. It does not necessarily means that significant narrowing is present, since blood vessels initially can remodel to accommodate blood flow.

The Coronary Calcium Scan is a non-invasive test, and should not be confused with the more invasive test named CT-angiogram, which involved injection of contrast media, gives a view of the coronary arteries and its narrowings. The CAC (coronary artery calcium) test takes actually only a few minutes. You lie down on the 'CT-table'. Images are made at different slices through the chest, while you hear the apparatus make spinning noises. In the process, also a chest X-ray is made.

Image (with permission) from a CAC-test.The white spots : on top part of the breastbone, at bottom : the vertebrae, the white spots right of the middle in the image, indicate calcium in the coronary arteries (LAD)

As a result of the test, a calcium score (often called Agatston score, potentially a variation thereof) is made which quantifies the amount of calcium in the coronary arteries. If all is well, your calcium score will actually be 0. You may be classified as having a score of no, minimal (1-10), mild (11-100), moderate (101-400) or severe (>400) calcium presence. The test may also give information about which of the coronary arteries are affected, which not (but not give a clear picture of narrowings as the CT-angiogram does).

With percentile data, you will also be told, how many people your age have lower or higher calcium scores. For example, if your percentile is equal to 30, it means 30 % of persons your age, have a lower score, and 70% have a higher score.

The Coronary Calcium Scan can give very useful information. It is most often recommended for persons at intermediate risk for cardiovascular disease, who are not having symptomes (smokers, poor lipid profile, diabetics, hypertensive persons, etc.). Young people with no symptoms, or people who already diagnosed with disease, are not directly candidates.

It is often stated, that a test should only be carried out, if action will be taken depending on the results. This also applies for the CAC-test. As suggested from the description above, often it will not be quite clear in advance, what the results will be (in asymptomatic people). If a high score is present, medication may be prescribed to prevent further inflammation and calcification in the future.

Importantly, and this is one of the reasons the test can be very useful, a ZERO score, can be very reassuring, and may save the scanned person from having to take numerous medications. We have to warn here though, that having a score test of 0, while reassuring (statistically, you have a much better chance of having no significant coronary heart disease in years to come, compared to people with a positive test), does not completely rule out plaque formation, since the plaque may not yet have been calcified.