From the Guidelines
The Agatston calcium score is calculated by measuring the amount of calcium in the coronary arteries using a CT scan, where the area of each calcified lesion is multiplied by a density factor and summed to produce the total score, as described in the study by 1. The calculation involves identifying areas of calcification in the coronary arteries and assigning a score based on both the area and density of the calcified plaques.
- The CT scan identifies calcified lesions with a density greater than 130 Hounsfield units.
- For each lesion, the area is multiplied by a density factor (1 for 130-199 HU, 2 for 200-299 HU, 3 for 300-399 HU, and 4 for ≥400 HU).
- These weighted scores for all lesions are then summed to produce the total Agatston score. The score typically ranges from 0 (no detectable calcium) to over 400 (extensive calcification), with higher scores indicating greater coronary artery calcification and increased cardiovascular risk, as supported by the study 1. This measurement is valuable because coronary artery calcification is strongly associated with atherosclerotic plaque burden and can help predict future cardiovascular events, allowing for more targeted preventive interventions, as noted in the study 1. The Agatston score can also be expressed as a percentile, adjusted for sex and race, providing a more personalized assessment of cardiovascular risk, as described in the study 1. Overall, the Agatston calcium score is a useful tool for assessing coronary artery calcification and predicting cardiovascular risk, and its calculation is based on a standardized method that takes into account the area and density of calcified lesions, as outlined in the study 1.
From the Research
Agatston Calcium Score Calculation
The Agatston calcium score is a measure used to assess the amount of calcium in the coronary arteries, which is an indicator of coronary artery disease. The score is calculated based on the amount of calcium detected in the coronary arteries during a computed tomography (CT) scan.
Calculation Method
- The Agatston score is calculated by multiplying the area of each calcified lesion by a factor based on the density of the lesion 2.
- The score is typically calculated using a non-contrast CT scan, but it can also be calculated using contrast-enhanced CT coronary angiography (CTA) images 3, 4.
- The calculation involves detecting and quantifying the amount of calcium in the coronary arteries, which can be done manually or using automated algorithms 4.
Factors Affecting the Score
- The Agatston score can be affected by various factors, including the presence of coronary artery stenosis and the composition of coronary artery plaques 5.
- Long-term statin therapy has been associated with an increased likelihood of severe coronary artery calcification, which can affect the Agatston score 6.
Correlation with Calcium Amount
- Studies have shown that the Agatston score is highly correlated with the amount of calcium in the coronary arteries, as measured by atomic absorption spectroscopy (AAS) 2.
- The score has also been shown to be correlated with macroscopic and histological assessments of coronary calcification and stenosis 2.