Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Mar;15(3):489-500.
doi: 10.1016/j.jcmg.2021.09.018. Epub 2021 Nov 17.

Mean Versus Peak Coronary Calcium Density on Non-Contrast CT: Calcium Scoring and ASCVD Risk Prediction

Omar Dzaye  1 , Alexander C Razavi  2 , Zeina A Dardari  3 , Daniel S Berman  4 , Matthew J Budoff  5 , Michael D Miedema  6 , Olufunmilayo H Obisesan  3 , Ellen Boakye  3 , Khurram Nasir  7 , Alan Rozanski  8 , John A Rumberger  9 , Leslee J Shaw  10 , Martin Bødtker Mortensen  11 , Seamus P Whelton  3 , Michael J Blaha  3
Affiliations

Mean Versus Peak Coronary Calcium Density on Non-Contrast CT: Calcium Scoring and ASCVD Risk Prediction

Omar Dzaye et al. JACC Cardiovasc Imaging. 2022 Mar.

Abstract

Objectives: This study sought to assess the relationship between mean vs peak calcified plaque density and their impact on calculating coronary artery calcium (CAC) scores and to compare the corresponding differential prediction of atherosclerotic cardiovascular disease (ASCVD) and coronary heart disease (CHD) mortality.

Background: The Agatston CAC score is quantified per lesion as the product of plaque area and a 4-level categorical peak calcium density factor. However, mean calcium density may more accurately measure the heterogenous mixture of lipid-rich, fibrous, and calcified plaque reflective of ASCVD risk.

Methods: We included 10,373 individuals from the CAC Consortium who had CAC >0 and per-vessel measurements of peak calcium density factor and mean calcium density. Area under the curve and continuous net reclassification improvement analyses were performed for CHD and ASCVD mortality to compare the predictive abilities of mean calcium density vs peak calcium density factor when calculating the Agatston CAC score.

Results: Participants were on average 53.4 years of age, 24.4% were women, and the median CAC score was 68 Agatston units. The average values for mean calcium density and peak calcium density factor were 210 ± 50 HU and 3.1 ± 0.5, respectively. Individuals younger than 50 years of age and/or those with a total plaque area <100 mm2 had the largest differences between the peak and mean density measures. Among persons with CAC 1-99, the use of mean calcium density resulted in a larger improvement in ASCVD mortality net reclassification improvement (NRI) (NRI = 0.49; P < 0.001 vs. NRI = 0.18; P = 0.08) and CHD mortality discrimination (Δ area under the curve (AUC) = +0.169 vs +0.036; P < 0.001) compared with peak calcium density factor. Neither peak nor mean calcium density improved mortality prediction at CAC scores >100.

Conclusion: Mean and peak calcium density may differentially describe plaque composition early in the atherosclerotic process. Mean calcium density performs better than peak calcium density factor when combined with plaque area for ASCVD mortality prediction among persons with Agatston CAC 1-99.

Keywords: atherosclerotic plaque; calcium density; cardiovascular disease; coronary artery calcium; multidetector computed tomography; primary prevention; risk; vascular calcification.

PubMed Disclaimer

Conflict of interest statement

Funding Support and Author Disclosures This project was supported in part by a research grant from the National Institutes of Health–National Heart, Lung, and Blood Institute (L30 HL110027). Dr Blaha has received grants from the National Institutes of Health, U.S. Food and Drug Administration, American Heart Association, and Aetna Foundation; grants and personal fees from Amgen; and personal fees from Sanofi, Regeneron, Novartis, Bayer, and Novo Nordisk outside the submitted work. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.

Figures

Figure 1.
Figure 1.. Association of mean and peak calcium density with age among all participants (A), women (B), and men (C).
The largest differences between mean and peak calcium values were among persons <50 years old, though the two calcium measures converged with older age.
Figure 2.
Figure 2.. Association of mean and peak calcium density with total plaque area burden.
Mean and peak calcium density most strongly differed among individuals with a total plaque area <100 mm2 but were more similar for those with a higher total plaque area burden.
Figure 3.
Figure 3.. Correlation between mean and peak calcium density, stratified by CAC score (A) and total plaque area burden tertiles (B).
Compared to individuals with CAC 100–399 and/or CAC >400, individuals with CAC 1–99 had a larger magnitude difference, but stronger correlation between mean and peak calcium density values. A similar pattern between mean and peak calcium density was observed across increasing total plaque area tertiles.
Figure 4.
Figure 4.. Calculation of coronary artery calcium scores with mean versus peak calcium density.
Recalculating CAC using mean calcium density resulted in a larger proportion of individuals with lower CAC scores.
Figure 5.
Figure 5.. Summary of differences and potential applications of mean versus peak calcium density.
Mean calcium density versus peak calcium density.
Central Illustration.
Central Illustration.. Mean versus peak calcium density in CAC scoring and mortality risk prediction.
Mean and peak calcium density are most strongly dissimilar among individuals with a total plaque area <100 mm2, and approximately 25% of individuals with an Agatston CAC score of 100–399 are downwardly reclassified into a CAC score group of 1–99 when scoring occurs with mean instead of peak calcium density. Mean calcium density performs better than peak calcium density for the prediction of ASCVD mortality for individuals with CAC 1–99.
See this image and copyright information in PMC

Comment in

References

    1. Arnett DK, Blumenthal RS, Albert MA, Buroker AB, Goldberger ZD, Hahn EJ, et al. 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease. J Am Coll Cardiol. 2019;74(10):e177–232. - PMC - PubMed
    1. Agatston AS, Janowitz WR, Hildner FJ, Zusmer NR, Viamonte M, Detrano R. Quantification of coronary artery calcium using ultrafast computed tomography. J Am Coll Cardiol. 1990. Mar 15;15(4):827–32. - PubMed
    1. Virmani R, Burke AP, Farb A, Kolodgie FD. Pathology of the Vulnerable Plaque. Journal of the American College of Cardiology. 2006. - PubMed
    1. Blaha MJ, Mortensen MB, Kianoush S, Tota-Maharaj R, Cainzos-Achirica M. Coronary Artery Calcium Scoring: Is It Time for a Change in Methodology? JACC: Cardiovascular Imaging. 2017. - PubMed
    1. Zaromytidou M, Antoniadis AP, Siasos G, Coskun AU, Andreou I, Papafaklis MI, et al. Heterogeneity of Coronary Plaque Morphology and Natural History: Current Understanding and Clinical Significance. Current Atherosclerosis Reports. 2016. - PubMed

Publication types