From the Guidelines
Yes, a high calcium score is predictive of atherosclerosis. Coronary artery calcium (CAC) scoring is a reliable indicator of the presence and extent of atherosclerotic plaque in the coronary arteries. The higher the calcium score, the greater the burden of atherosclerosis and the higher the risk for future cardiovascular events. A score of zero indicates no detectable calcified plaque and very low cardiovascular risk, while scores above 100 suggest moderate plaque burden, and scores above 400 indicate extensive atherosclerosis with high risk for coronary events.
Key Points
- Calcium scoring works because atherosclerosis involves inflammation and healing processes that eventually lead to calcium deposition in arterial walls.
- This calcification represents more advanced stages of plaque development and can be detected by CT scanning before symptoms occur.
- The predictive value of calcium scoring is independent of traditional risk factors, making it particularly useful for reclassifying intermediate-risk patients into more appropriate risk categories for preventive interventions.
- However, it's essential to note that while calcium scoring detects calcified plaque, it cannot identify non-calcified "soft" plaque that may also cause heart attacks.
Evidence-Based Recommendation
The most recent and highest quality study, 1, suggests that CAC scoring can inform patient-clinician discussions about treatment options versus associated risks. Another study, 1, found that a calcium score of >100 had a 2.2 times higher risk for all-cause mortality, 4.3 times higher cardiovascular-specific mortality, and 10.4 times higher risk of coronary heart disease, than patients with a zero calcium score.
Clinical Implications
- CAC scoring should be considered for asymptomatic patients at intermediate risk for coronary artery disease, as it can provide incremental prognostic information over conventional risk factors.
- The presence of any measurable coronary calcium is independently related to hard and soft events in men and women at low to intermediate pretest risk.
- A positive calcium score can restratify asymptomatic patients with a family history of premature CAD to a high-risk category and can even reclassify those individuals without risk factors as higher risk than those with multiple risk factors but no coronary artery calcification.
From the Research
Relationship Between Calcium Score and Atherosclerosis
- A high calcium score is strongly associated with an increased risk of cardiovascular disease (CVD) events 2, 3, 4, 5, 6
- The absence of coronary artery calcium (CAC) is associated with a low long-term risk of CVD, even among groups classified as high risk based on traditional risk factors 3
- A coronary calcium score of 400 or higher is a reliable, noninvasive predictor of the progression of coronary artery diseases and their consequences, including major adverse cardiovascular events (MACE) 4
Predictive Value of Calcium Score
- CAC scoring may be used to clarify atherosclerotic cardiovascular disease (ASCVD) risk in patients with severe hypercholesterolemia 5
- A higher CAC category is associated with increased statin use after CAC scoring 5
- Patients with CAC scores >300 are at an equivalent risk of MACE and its components as those treated for established ASCVD 6
Clinical Implications
- The guideline-based role of CAC in allocation of CVD prevention therapies has expanded to include both statin and non-statin medications 3
- CAC scoring may be used to identify high-risk patients most likely to benefit from pharmacotherapies 3
- Understanding the CAC scores that are associated with ASCVD risk equivalent to stable secondary prevention populations may be important for guiding the intensity of preventive approaches more broadly 6