Calcium Score, or fully known as CT Coronary Calcium Score, is a test to detect ‘calcium deposits in the coronary arteries’ using a computed tomography (CT Scan) to examine the ‘degeneration’ of the coronary arteries and assess the ‘risk’ of developing coronary artery disease in the future, even without symptoms.
Advantages of Coronary Artery Calcium Detection (Calcium Score)
- Highly accurate in assessing the risk of coronary artery stenosis, helping to plan timely prevention or treatment
- Simple, painless, and quick
- No need for contrast injection, low radiation exposure, safe
- Affordable
How is Calcium Score different from Exercise Stress Test (EST)?
Since coronary artery stenosis progresses slowly from mild to severe narrowing as a gradual degeneration process, eventually leading to atherosclerosis in the late stage and resulting in coronary artery stenosis, blockage, or rupture, Calcium Score testing can detect changes or degeneration of the arteries from the early stage.
From the image, it can be seen that the coronary arteries begin to change from a ‘normal artery state’ (far left of the image) with accumulation of fat and calcium deposits on the artery walls, which causes ‘gradual artery narrowing’ (second part of the image). This degeneration process takes many years, possibly 5-30 years, depending on the risk factors accelerating artery degeneration.
When patients have severe artery narrowing or blood clots causing blockage (two parts on the right side of the image), it is considered the stage when patients have symptoms and need to see a doctor. This is the late stage of artery degeneration in that area, making treatment more difficult.
Exercise Stress Test (EST) is a test to detect ischemia while the patient exercises or the heart works hard. Severely narrowed arteries reduce blood flow, causing chest pain and changes in the electrocardiogram during exercise or heart stress. The results are generally as follows:
- EST detects abnormalities only when the coronary arteries are already severely narrowed
- Calcium Score (CAC) can detect abnormalities of arteries with calcium deposits on the walls from mild to severe narrowing
Therefore, CAC is a test that can detect ‘degeneration’ of the coronary arteries from the early stage before symptoms appear, helping to assess the ‘risk’ of future heart disease quickly and accurately, leading to appropriate management or treatment to reduce the risk of coronary artery disease.
Relationship between Calcium Score and Future Heart Disease Risk
Besides detecting calcium deposits, the Calcium Score test indicates artery degeneration, similar to gray or thinning hair showing scalp aging. The amount of calcium found correlates with the plaque burden in the arteries; the higher the score, the more severe the artery degeneration.
Most importantly
“The amount of calcium detected clearly indicates the risk
of developing heart disease in the next 5-10 years”
The medical community worldwide has known this fact for over 20 years, with studies in the US and Europe. In Thailand, many medical professors also pay attention and emphasize this. For example, data from the American MESA study, conducted for over 20 years with more than 2,000 published papers, highlights important points such as:
People with a Calcium Score (CAC) of 0 have less than 1% chance of heart disease in 5 years, while those with CAC over 300 have more than 10% chance
Coronary artery degeneration or coronary artery disease is not an overnight process but takes many years before symptoms appear. Detecting it late when symptoms occur may mean “we found it too late.” The effort to detect artery degeneration before symptoms for care, delay, and prevention is the main concept of the Calcium Score test, which is very important and beneficial.
Dr. Somrung Chotinuramon
Cardiology Specialist
Heart Center, Phyathai 1 Hospital
