Hidden Heart Risk? Understanding Coronary Artery Calcium Scoring and Why It Matters

Despite knowing common risk factors of heart disease, some people may still develop heart disease without obvious symptoms. This is why doctors are increasingly using tests that can identify hidden signs of cardiovascular disease before a heart attack or stroke occurs. One such test is coronary artery calcium (CAC) scoring, which is a simple, non-invasive scan that helps assess the amount of calcium build-up in the arteries supplying blood to the heart. The results can give valuable information about a person's future risk of heart disease and help guide treatment decisions.

What Is Coronary Artery Calcium Scoring?

Coronary artery calcium scoring is a specialised CT scan that looks for calcium deposits in the coronary arteries, the blood vessels that supply oxygen-rich blood to the heart muscle.

Calcium itself is not harmful, but its presence inside the artery walls usually indicates a build-up of fatty plaque, a condition known as atherosclerosis. Over time, these plaques can narrow the arteries or suddenly rupture, leading to a heart attack.

The scan measures the amount of calcium present and provides a numerical result known as the calcium score. A higher score generally means a greater amount of plaque and a higher risk of future heart disease.

Why Does Calcium Build Up In The Arteries?

Healthy arteries are smooth and flexible, allowing blood to flow easily. However, years of exposure to risk factors can damage the artery walls.

As cholesterol, fats, and inflammatory cells accumulate, plaques begin to form. With time, some of these plaques become hardened by calcium deposits.

Although calcium helps strengthen bones and teeth, calcium inside the coronary arteries is a sign that atherosclerosis has developed.

Why Is The Test Important?

Many people with early coronary artery disease do not experience any symptoms. They may feel perfectly well while plaque gradually builds up inside their arteries. According to a study published in the Journal of Cardiovascular Development and Disease, coronary artery calcium scoring helps identify this hidden disease before symptoms appear.

The test can:

• Detect early coronary artery disease.
• Estimate the future risk of heart attack.
• Help doctors decide whether preventive treatments are needed.
• Encourage people to adopt healthier lifestyles.
• Reduce unnecessary medication in people with very low risk.

It is considered a useful tool for assessing cardiovascular risk in selected individuals.

Who Should Consider A Coronary Artery Calcium Scan?

According to Dr Deebanshu Gupta, Cardiologist at Sarvodya Hospital, Jalandhar, “This test is not recommended for everyone.”

Doctors may suggest coronary artery calcium scoring for adults who have an intermediate risk of developing heart disease, especially when it is unclear whether cholesterol-lowering medicines such as statins are needed.

• It may be considered for people who:
• Have borderline or moderately high cholesterol.
• Have a family history of early heart disease.
• Have high blood pressure.
• Have diabetes or prediabetes.
• Smoke or have smoked in the past.
• Have several cardiovascular risk factors but no symptoms.

The decision to have the scan should always be made after discussing individual risk factors with a healthcare professional.

Who May Not Benefit From The Test?

The scan is generally not useful for everyone.

It is usually not recommended for:

• People already diagnosed with coronary artery disease.
• Individuals who have previously had a heart attack or coronary stent.
• People with symptoms such as chest pain who require different diagnostic tests.
• Young adults with a very low risk of heart disease.
• The scan is designed mainly for risk assessment rather than diagnosing active heart problems.

What Happens During The Scan?

According to the American Heart Association, a coronary artery calcium scan is quick, painless, and does not require injections or special preparation in most cases. Here is the step-by-step procedure:

• You lie on a scanning table.
• Small sticky patches are placed on your chest to monitor your heartbeat.
• The table moves through a CT scanner.
• You may be asked to hold your breath for a few seconds while images are taken.
• The entire procedure usually takes about 10 to 15 minutes.

Because it uses CT imaging, there is exposure to a small amount of radiation. However, the radiation dose is relatively low.

Understanding The Calcium Score

The scan produces a calcium score that reflects the amount of calcified plaque in the coronary arteries. We took reference from The Egyptian Heart Journal, to collate different calcium scores and what they may indicate.

Score of 0
A score of zero means no detectable calcium was found.
This usually suggests a very low risk of heart attack over the next several years, although it does not completely rule out future heart disease.

Score of 1 to 99
This indicates a small amount of calcium and mild plaque build-up.
The risk of heart disease is higher than someone with a score of zero, but lifestyle improvements may help reduce future risk.

Score of 100 to 399
This suggests moderate plaque build-up and a significantly increased risk of coronary artery disease.
Doctors often recommend more intensive risk factor management, which may include cholesterol-lowering medication.

Score of 400 or higher
A very high score indicates extensive calcium deposits and a high likelihood of significant coronary artery disease.

Further evaluation and aggressive management of cardiovascular risk factors are usually needed.

Also Read: Can Childhood Habits Increase Future Heart Disease Risk?

Can Coronary Artery Calcium Score Predict A Heart Attack?

“A coronary artery calcium score cannot predict exactly when or if someone will have a heart attack. However, it provides valuable information about overall cardiovascular risk,” shares Dr Gupta.

According to a study published in the journal 'Circulation: Cardiovascular Imaging', people with higher scores have a greater chance of developing coronary artery disease and experiencing future cardiovascular events compared with those who have little or no calcium.

The score helps doctors estimate long-term risk rather than diagnose an immediate emergency.

Can Coronary Artery Calcium Be Removed?

Once calcium deposits have formed, they cannot usually be removed.

However, treatment aims to prevent further plaque build-up and reduce the risk of heart attack.

This involves controlling risk factors and slowing disease progression rather than eliminating existing calcium.

Are There Any Limitations of CAC Test?

Coronary artery calcium scoring is a valuable test, but it has limitations.

• It only detects calcified plaque and may not identify very early soft plaques that have not yet developed calcium.
• The test also does not show how severely an artery is narrowed or whether blood flow is currently reduced.
• For people with symptoms suggestive of heart disease, other investigations such as stress tests or coronary CT angiography may be more appropriate.

Final Word

Coronary artery calcium scoring is a simple CT scan that measures calcium deposits in the coronary arteries, providing an early indication of hidden coronary artery disease. It is particularly useful for people with an intermediate risk of heart disease, helping doctors make informed decisions about preventive treatment and lifestyle changes. Although the scan cannot prevent heart disease on its own, it offers valuable insight into cardiovascular health before symptoms appear.