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.