Coronary Artery Calcium (CAC) Scan

A Coronary Artery Calcium (CAC) scan is a non-invasive medical imaging test used to detect and measure the amount of calcium in the coronary arteries, which supply blood to the heart. The test is also known as a coronary calcium scan or cardiac CT scan.

Purpose

The primary purpose of a CAC scan is to assess the risk of coronary artery disease (CAD) and to identify individuals who may be at high risk for a heart attack or other cardiovascular events. The test can help doctors:

• Detect early signs of CAD, even in asymptomatic patients
• Assess the severity of CAD
• Monitor the progression of CAD over time
• Guide treatment decisions, such as the need for lifestyle changes, medication, or further testing

Procedure

A CAC scan is typically performed using a computed tomography (CT) scanner. The procedure involves:

• Lying on a table that slides into the CT scanner
• Removing any metal objects, such as jewelry or clothing with metal fasteners
• Wearing a gown and lying still during the scan
• The CT scanner taking multiple X-ray images of the heart from different angles
• The test typically takes around 10-15 minutes to complete

Results

The results of a CAC scan are usually reported as a coronary calcium score, which indicates the amount of calcium present in the coronary arteries. The scores are categorized as follows:

• 0: No calcium detected (low risk)
• 1-10: Minimal calcium detected (low to moderate risk)
• 11-100: Moderate calcium detected (moderate risk)
• 101-400: Increased calcium detected (high risk)
• Above 400: Extensive calcium detected (very high risk)

Risks and Limitations

While a CAC scan is generally considered safe, there are some risks and limitations to be aware of:

• Radiation exposure: The CT scanner uses X-rays, which involve radiation exposure. However, the dose is typically low.
• Allergic reactions: Some people may be allergic to the contrast dye used in the scan.
• False positives: The test may detect calcium in people who do not have CAD.
• False negatives: The test may not detect CAD in people who have it.

Who Should Get a CAC Scan

A CAC scan is typically recommended for individuals who:

• Are at high risk for CAD, such as those with a family history or multiple risk factors (e.g., high blood pressure, high cholesterol, smoking)
• Have symptoms of CAD, such as chest pain or shortness of breath
• Have been diagnosed with CAD and need to monitor the progression of the disease
• Are considering starting a new exercise program or making significant lifestyle changes

Insurance Coverage

Insurance coverage for CAC scans varies depending on the individual's insurance plan and medical history. Some insurance plans may cover the test as a preventive service, while others may require a copayment or coinsurance.

Frequently Asked Questions (FAQs)

What is a Coronary artery calcium (CAC) scan?
A non-invasive test that uses computed tomography (CT) to detect and measure calcium buildup in coronary arteries.

Why is a CAC scan performed?
To assess the risk of heart disease, typically for individuals with intermediate risk or those with symptoms such as chest pain.

How is a CAC scan done?
The patient lies on a table that slides into a CT scanner, which takes images of the coronary arteries.

Does a CAC scan use radiation?
Yes, it uses low-dose radiation from the CT scanner.

Are there any preparations needed for a CAC scan?
Typically, no special preparation is required, but patients may be asked to avoid caffeine and nicotine before the test.

What are the risks associated with a CAC scan?
Generally considered low-risk, but may include radiation exposure and allergic reactions to contrast material, if used.

Can a CAC scan diagnose heart disease?
It can detect calcium buildup, which may indicate heart disease, but further testing may be needed for a definitive diagnosis.

How long does a CAC scan take?
Typically around 10-15 minutes to complete the scan.

Will a CAC scan require contrast material?
Usually not required, but may be used in some cases to enhance image quality.

Can anyone have a CAC scan?
Generally recommended for adults aged 40-75 with intermediate risk of heart disease, but may not be suitable for everyone, such as those with severe kidney disease.