What is a Coronary Artery Calcium (CAC) score test?

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From the Guidelines

A coronary calcium score test is a crucial, non-invasive heart scan that checks for calcium buildup in the arteries, providing vital information to assess the risk of heart attack or other heart problems. This test uses a special type of X-ray called a CT scan that takes pictures of your heart in just a few minutes while you lie on a table, as described in the study by 1. The calcium that the test looks for isn't from your diet but rather from a process called atherosclerosis, where plaque builds up in your artery walls, containing calcium that appears as bright white spots on the scan. The more calcium found, the higher your score, ranging from zero (no detectable calcium) to over 400 (extensive buildup), with higher scores indicating a greater risk of having a heart attack or other heart problems in the future, as supported by the findings of 1 and 1. Some key points to consider about the coronary calcium score test include:

  • The test doesn't require any special preparation, injections, or dyes, and you'll be exposed to a relatively small amount of radiation, making it a safe and convenient option.
  • It's particularly useful for people between 40-70 years old who have risk factors like high blood pressure, high cholesterol, diabetes, smoking history, or family history of heart disease but don't yet have symptoms, as noted in the guidelines by 1.
  • Your doctor can use your calcium score, along with other health information, to decide if you need medications like statins or lifestyle changes to lower your heart disease risk, with the goal of reducing morbidity, mortality, and improving quality of life.
  • A coronary calcium score of zero identifies individuals at lower risk of ASCVD events and death over a >10-year period, as found in the study by 1, which can help guide shared decision-making about statins or other preventive interventions.

From the Research

What is a Coronary Calcium Score Test

  • A coronary calcium score test is a medical imaging test that uses a computed tomography (CT) scan to detect and measure the amount of calcium in the coronary arteries, which supply blood to the heart 2.
  • The test is used to assess the risk of cardiovascular disease and to guide preventive therapy, such as statins and aspirin, in asymptomatic individuals 2, 3.

How the Test Works

  • The test uses a CT scanner to take pictures of the coronary arteries and detect any calcium deposits, which are a sign of atherosclerosis (hardening of the arteries) 4.
  • The amount of calcium is then measured and given a score, known as the Agatston score, which ranges from 0 to over 400 4.
  • A score of 0 indicates no calcium deposits and a low risk of cardiovascular disease, while higher scores indicate more extensive calcium deposits and a higher risk of cardiovascular disease 2, 3.

Benefits and Limitations of the Test

  • The test is non-invasive, painless, and relatively quick, taking only a few minutes to complete 5.
  • It is also cost-effective, especially in asymptomatic individuals, and can help identify those who are at high risk of cardiovascular disease and may benefit from preventive therapy 2, 3.
  • However, the test is not perfect and may not detect all cases of cardiovascular disease, especially in individuals with non-calcified plaque components 6.
  • Additionally, the test may not be necessary for individuals who have already had a non-gated chest CT, as the presence or absence of coronary calcium can often be estimated from these images 4.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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