The Coronary Artery Calcium (CAC) score is a numerical value derived from a non-invasive computed tomography (CT) scan of the heart. This score quantifies the amount of calcified plaque within the walls of the coronary arteries, which supply blood to the heart muscle. The presence of calcium signifies long-standing plaque buildup, the underlying cause of atherosclerotic cardiovascular disease (ASCVD). A higher CAC score correlates with a greater burden of coronary plaque and an increased long-term risk of a major cardiac event, such as a heart attack or stroke. The CAC test refines an individual’s cardiovascular risk assessment, guiding preventive treatment decisions.
Understanding the Nature of Coronary Calcium
A CAC score above zero indicates that the atherosclerotic process has advanced, resulting in calcified plaque—hardened scar tissue within the artery wall. This calcification is a complex biological process occurring in response to arterial injury and inflammation. The physical calcium measured by the scan is chemically stable and dense.
Once coronary plaque has calcified, the physical calcium deposits are considered irreversible. Therefore, the measured CAC score is highly unlikely to decrease over time through lifestyle changes or medical therapies. The goal of management shifts away from reducing the numerical score and toward stabilizing existing plaque and preventing disease progression. Stabilizing plaque means turning an unstable lesion into a dense, fibrous, and less volatile one, significantly reducing the probability of a heart attack.
Aggressive risk factor management aims to slow the rate at which new plaque forms and calcifies. A high CAC score serves as a powerful early warning sign that necessitates immediate intervention to lower future event risk, even if the score remains elevated.
Primary Lifestyle Modifications to Slow Progression
Lifestyle modifications are the most immediate and powerful steps an individual can take to impact the risk factors driving coronary plaque progression. Dietary management focuses on adopting an eating pattern low in saturated and trans fats, which increase harmful LDL cholesterol levels. Following a Mediterranean-style diet, rich in fruits, vegetables, whole grains, and healthy fats like olive oil, reduces cardiovascular risk factors.
Increasing soluble fiber intake (10 to 25 grams daily) helps bind cholesterol in the digestive system, aiding in lipid control. Regular physical activity is foundational for slowing disease progression, as it improves endothelial function and lowers blood pressure. Guidelines recommend at least 150 minutes per week of moderate-intensity aerobic exercise or 75 minutes of vigorous-intensity exercise.
Incorporating resistance training on two or more days each week is also beneficial for cardiovascular health. For tobacco users, smoking cessation is the single most impactful action for halting plaque progression and reducing cardiac event risk, with benefits seen almost immediately. Weight management is important, as maintaining a healthy body mass index (BMI) helps manage blood pressure and cholesterol levels.
Pharmacological Strategies for Risk Management
Pharmacological therapy is necessary for most patients with a positive CAC score, working alongside lifestyle changes to address atherosclerosis. Statins form the cornerstone of this treatment strategy due to their dual action. Their primary role is aggressively lowering LDL cholesterol, which reduces the material available for plaque formation.
Statins also have a pleiotropic effect, including potent anti-inflammatory and plaque-stabilizing properties within the arterial wall. High-intensity statin therapy is often initiated to achieve very low LDL cholesterol targets, regardless of baseline levels, because a high CAC score indicates established disease. Although statin use may be associated with a continued rate of calcification, this is considered a benign effect of plaque stabilization, resulting in a clear overall reduction in heart attack risk.
Controlling hypertension is another focus, often requiring medications such as Angiotensin-Converting Enzyme (ACE) inhibitors or Angiotensin II Receptor Blockers (ARBs). These drugs relax blood vessels and lower blood pressure, reducing mechanical stress on arterial walls and slowing further injury. For individuals with co-existing conditions, specific medications manage blood sugar (targeting an HbA1c below 7% for diabetics) or high triglycerides. A high CAC score often mandates aggressive medical therapy to prevent future cardiovascular events.
Long-Term Follow-Up and Advanced Testing
Effective management of a positive CAC score requires a long-term, structured approach involving close monitoring and periodic reassessment of risk factors. Regular check-ups should include annual lipid panels to ensure LDL cholesterol targets are maintained, along with consistent monitoring of blood pressure and blood sugar control. These visits focus on confirming adherence to both lifestyle and pharmacological regimens.
Serial CAC scans are generally not recommended for tracking treatment efficacy due to the score’s irreversible nature. However, a positive CAC score may necessitate additional non-invasive testing, especially if the score is very high (over 400) or if the patient develops symptoms like chest pain. Advanced tests, such as an exercise stress test or a CT angiography (CTA), assess functional blood flow and determine if calcified plaque has caused a significant blockage. These measures ensure the medical strategy is effectively reducing cardiac event risk and that dangerous blockages are identified.