What is Calcium Scoring?
It is a technique to obtain Coronary Artery Calcium (CAC) Score using a Computed Tomography (CT) scanner.

The amount of calcium in the heart arteries can be quantified using either an electron-beam CT (EBCT) or multiow-detector CT (MDCT). This is a highly advanced non-invasive technology that uses a high speed CT scanner and most advanced computer software to detect and measure the amount of calcium in the coronary arteries. Recent studies have shown good correlation between both imaging modalities.

Presence of coronary calcium means the presence of an atherosclerotic plaque. It is not usually found in healthy coronary vessels. On the other hand, atherosclerotic plaques do not necessarily show calcification.

We can estimate the amount of calcium present by means of calcium scoring methods e.g. Agatston or Volume scores. The value of calcium score is improved when it is ranked according to a person’s age and sex.

How useful is Coronary Artery Calcium Scoring as an added tool for cardiovascular risk assessment?
Coronary Artery Disease (CAD) ‘atherosclerotic narrowing of the heart blood vessels’ is the most common cause of admission and deaths in most countries including Malaysia. Patients with established CAD require specialized care and treatment from their cardiologists.

The grim statistics of CAD plus the fact that one-third of persons with heart disease have heart attack initially. Of these about 25 percent may not reach medical care in time and hence do not survive their first attack.

Hence, one of the aims of preventive cardiology is to detect CAD in apparently healthy individuals and identify those at risk of developing CAD. By instituting life-style modification and pharmacological intervention in these high risk individuals, we hope to reduce the risk of a cardiovascular event and perhaps slow or regress the atherosclerotic disease.

One of the most commonly used risk prediction tools is based on the person’s risk factors, e.g. sex, age, raised cholesterol, diabetes mellitus, smoking and blood pressure. The commonly used scoring models include the Framingham risk score and Euroscore.
However, coronary risk scores can explain only 70 percent of the overall risk for CAD. In patients with low-intermediate risks, new strategies to better delineate their risk is needed. One of these emerging strategies is the quantification of coronary artery calcium.
The recent European Guideline on Cardiovascular Disease Prevention 2003 states that calcium score “is an important parameter to detect asymptomatic individuals at high risk for future CVD events, independent of the traditional risk factors.”

How safe is a CT Scan for Coronary Artery Calcium Score?
CAC scanning with a CT scanner is safe and involves only a low radiation dose (1.5 - 2.4mSv). This would in general term translate to a lifetime risk of developing life-threatening cancer of only 0.0038-0.0060%.

Why should I have a CT Scan for Coronary Artery Calcium Score investigation?
The published literature todate does not define clearly who deserves or benefits from a calcium score assessment. There is, however, a general agreement that calcium score would be useful in persons with significant coronary risk factors and deemed to have low to intermediate probability of disease. It is hoped that by identifying the presence of atherosclerosis (cholesterol plaque deposits in the heart vessels), one can initiate effective lifestyle measures or treatments to prevent a serious/fatal cardiac event.

Who should have a CT Scan for Coronary Artery Calcium Score?
Anyone above the age of 45 years (male) and 55 years (female) and you may have the following features:

* High LDL cholesterol
* Low HDL cholesterol
* Family history of CAD
* High blood pressure
* Smoking
* Overweight / Obesity
* Diabetes
* Physical inactivity or a sedentary lifestyle

How is the CT Scan for Coronary Artery Calcium Score done?
Breath-holding instructions will be given. With our most advanced CT scanner, you will only need to hold your breath for a few seconds during the heart scanning. It’s fast, painless and non-invasive.

Our doctor and radiographer will then process the images and measure your calcium score. The score will be compared to standards for your age and sex. Your doctor will then discuss the results with you.

How can I prepare for a CT Scan for Coronary Artery Calcium Score?
There is no preparation required. You will lie down on the imaging table and ECG electrodes will be placed on your body.

How long does a CT Scan for Coronary Artery Calcium Score take?
The total scanning procedure takes less than 5 minutes.

What happens after the scan?
There is nothing much to anticipate after the scan. Once you have completed the scan, you may move on to your next program or test.

Are there any possible complications?
There is no known complication directly related to the scanning procedure.

What does it mean if my scan is positive?
A positive scan means that you have cholesterol deposits in the heart vessels. It does not, however tell you how badly the vessels are narrowed. Studies have shown that the higher one’s calcium score is, the higher his/her risk of a cardiac event like heart attack, death or need for procedures like angioplasty or bypass surgery.

Does a negative scan mean I am free from any cardiovascular disease?
A negative calcium score indicates that the possibility of you having a severe narrowing of the heart vessels is extremely low. It does not mean that you have no atherosclerotic disease. That is because some cholesterol plaques do not have calcium deposits. A CT coronary angiography would be better to detect such deposits. Nevertheless, the absence of calcium deposits may suggest a low likelihood of cardiac event like heart attack over the next 2-5 years.