The Coronary Artery Calcium (CAC) score is a non-invasive tool used by physicians to estimate an individual’s long-term risk of experiencing a heart attack or stroke. This specialized test assesses the presence and amount of calcified plaque within the walls of the heart’s arteries. The presence of this calcium is a direct indicator of atherosclerosis, the underlying disease process that leads to coronary artery disease. The CAC score helps gauge the progression of heart disease before symptoms, such as chest pain, become apparent, informing preventive treatment strategies tailored to a person’s specific level of risk.
How the Coronary Artery Calcium Test Works
The CAC test utilizes a specialized imaging technique called a computed tomography (CT) scan to capture detailed cross-sectional images of the heart. This procedure is non-invasive and does not require the injection of any contrast dye. Electrodes are placed on the chest to synchronize the scan with the patient’s heartbeat, ensuring the images of the coronary arteries are clear and motion-free.
The CT scanner detects dense, bright white spots within the arterial walls, which correspond to calcium deposits. Calcium accumulates in the fatty plaque over time as a consequence of chronic inflammation and injury within the artery. The test measures the total volume and density of these calcified lesions. The greater the amount of calcium detected, the more extensive the underlying atherosclerotic plaque buildup is.
Interpreting the Calcium Score Ranges
The numerical result of the scan is calculated using a method known as the Agatston Score, which combines the area and density of the detected calcium spots across all four major coronary arteries. A score of zero signifies that no calcified plaque was detected, placing the individual in an extremely low-risk category for a cardiac event over the next decade. This result is strongly associated with an excellent prognosis, often leading to a reassessment of whether cholesterol-lowering medications are necessary.
Scores ranging from 1 to 100 indicate a mild but definite presence of calcified plaque, suggesting early-stage coronary artery disease. This level of calcification is considered a low to moderate risk, often prompting a detailed discussion between the patient and physician about intensified lifestyle modifications.
When the score falls between 101 and 400, it represents a moderate plaque burden and a relatively high risk of a future cardiac event within the next three to five years. At this stage, medical intervention is typically initiated to aggressively manage modifiable risk factors.
A score exceeding 400, or especially one over 1,000, signals an extensive amount of calcified plaque throughout the coronary arteries. This substantial score represents a high to very high risk, indicating significant underlying coronary artery disease is present. Patients in this range have a strong likelihood of having one or more arteries narrowed by plaque, necessitating immediate and comprehensive medical management and further diagnostic evaluation.
Medical Management Following a High Score
Following a finding of a moderate or high coronary artery calcium score, medical management focuses on aggressive risk reduction to stabilize existing plaque and prevent future events. Physicians will often initiate pharmacological therapy aimed at lowering harmful cholesterol levels and reducing inflammation. High-intensity statins are commonly prescribed to achieve a significant reduction in low-density lipoprotein cholesterol (LDL-C), often targeting levels below 70 mg/dL, or even lower in cases of very high scores.
In addition to lipid-lowering agents, low-dose aspirin therapy (81 milligrams daily) may be recommended to reduce the risk of blood clot formation, though this decision is weighed against the risk of bleeding. The high score also necessitates a more thorough diagnostic workup to evaluate the functional impact of the plaque. This often includes advanced lipid panels, blood pressure monitoring, and functional tests like an exercise stress test to determine if the plaque is obstructing blood flow to the heart muscle during exertion.
Lifestyle Changes to Address Arterial Plaque
Alongside medical interventions, implementing significant lifestyle changes is foundational to slowing the progression of atherosclerosis. Dietary adjustments focus on adopting a heart-healthy eating pattern, such as the Mediterranean diet, which emphasizes fruits, vegetables, whole grains, and healthy fats like olive oil. Reducing the intake of saturated and trans fats found in processed foods and red meats helps decrease the building blocks of new plaque formation.
Regular physical activity guidelines suggest at least 150 minutes of moderate-intensity aerobic exercise per week, such as brisk walking. Consistent exercise helps improve blood pressure, increase beneficial high-density lipoprotein cholesterol, and maintain a healthy body weight. For individuals who use tobacco products, achieving complete smoking cessation is the most impactful single action for cardiovascular health, as smoking severely damages the arterial lining and accelerates plaque accumulation.