Highlight
- Nongated chest CT scans for coronary artery calcium (CAC) scoring strongly correlate with standard gated scans (r=0.961), enabling accurate cardiovascular risk prediction.
- Moderate and severe CAC detected on nongated scans are associated with significantly increased risk of coronary heart disease and cardiovascular events.
- Prognostic performance metrics (AUC, C-statistic, Brier score) for nongated CAC measures are comparable to gated CAC, supporting clinical utility.
- Incorporation of incidental CAC quantification from nongated scans aligns with upcoming 2026 ACC/AHA dyslipidemia guidelines, enhancing personalized preventive strategies.
Study Background
Coronary artery calcium (CAC) scoring is an established marker of atherosclerotic burden and predictive indicator of future coronary heart disease (CHD) and cardiovascular disease (CVD) events. Traditionally, CAC quantification is performed using gated cardiac computed tomography (CT) scans optimized to minimize cardiac motion artifacts. Despite the prognostic value of CAC, gated scans are not routinely performed in all clinical settings due to cost, availability, and radiation concerns. In contrast, nongated chest CT scans are widely performed for various clinical indications, often capturing incidental CAC. The clinical utility of CAC assessment from these nongated scans remains unclear due to concerns about motion, image quality, and scoring accuracy. The Multi-Ethnic Study of Atherosclerosis (MESA) provides a unique opportunity to directly compare CAC scoring from paired gated and nongated chest CT images and evaluate their respective prognostic value for cardiovascular events in a large, multiethnic cohort.
Study Design
This prospective study analyzed data from 2601 MESA participants who underwent same-day gated and nongated chest CT scans between April 2010 and December 2011 during the study’s exam 5. Participants without prior coronary heart disease or cardiovascular disease and with complete covariates (n=2472) were included in the analysis. Both types of CT scans were separately analyzed by a core laboratory blinded to scan type to quantify CAC. Participants were followed longitudinally for incident coronary heart disease and cardiovascular disease events. The association of gated and nongated CAC scores with outcomes was assessed using Cox proportional hazards models. Statistical concordance between gated and nongated CAC was evaluated using Pearson correlation coefficients. Model discrimination and accuracy were examined via receiver operating characteristic (ROC) curves, C-statistics, and Brier scores.
Key Findings
Among 2472 participants, the cohort was 53% female with diverse ethnic representation: 38% White, 13% Chinese, 26% Black, and 23% Hispanic/Latino. The distribution of CAC was categorized into zero, mild, moderate (101-299), and severe (≥300) scores. Compared with participants with zero CAC, those with moderate nongated CAC had a hazard ratio (HR) of 2.67 (95% CI: 1.14-6.27) for coronary heart disease, increasing to 5.22 (95% CI: 2.37-11.5) for severe CAC. Similarly, cardiovascular disease risk increased (HR 1.32 [95% CI: 1.32-4.04] for moderate and 2.89 [95% CI: 1.68-4.96] for severe CAC). Importantly, gated and nongated log-transformed CAC values were highly correlated (r=0.961; P<0.001). Areas under the ROC curves, C-statistics, and Brier scores reflecting predictive performance did not differ significantly between gated and nongated CAC assessments, confirming comparability in prognostic accuracy.
Expert Commentary
This study compellingly demonstrates that CAC scoring from widely available nongated chest CT scans can reliably predict cardiovascular outcomes and perform on par with traditional gated protocols. These findings address an important clinical gap given the high volume of nongated chest CTs performed annually for pulmonary, oncologic, and other indications. Leveraging incidental CAC data from existing scans could facilitate earlier risk stratification and targeted preventive interventions without additional radiation or costs. Importantly, the study’s diverse cohort enhances generalizability across populations. However, further work is needed to standardize scoring protocols for nongated images across institutions and to evaluate cost-effectiveness in routine clinical workflows.
Notably, in light of the 2026 American College of Cardiology/American Heart Association dyslipidemia guidelines endorsing the use of incidental CAC from nongated CTs, this study supports the clinical incorporation of such data to guide lipid-lowering therapy decisions and personalize cardiovascular risk management.
Conclusion
The high correlation and prognostic equivalence of coronary artery calcium scores obtained from nongated versus gated chest CT scans reinforce the value of incidental CAC quantification in cardiovascular risk assessment. Given the scalability of this approach and alignment with forthcoming guidelines, routine extraction of CAC scores from nongated CTs could significantly expand access to personalized preventive care for atherosclerotic cardiovascular disease. Ensuring standardized acquisition and interpretation methods, combined with prospective validation in diverse real-world populations, will be critical to integrating this strategy into clinical practice.
Funding and ClinicalTrials.gov
This research was supported by the Multi-Ethnic Study of Atherosclerosis (MESA) funded by the National Heart, Lung, and Blood Institute (NHLBI). The study is registered at ClinicalTrials.gov (NCT00005487).
References
- Verghese D, Trujillo R, Abraham D, et al. Predictive Value of Coronary Artery Calcium Score From Nongated Chest CT Scans Compared With Gated Scans and Incidence of Cardiovascular Events. Circulation. 2026 Jul 27;154(4):302-312. PMID: 42507772.
- Budoff MJ, Young R, Lopez VA, et al. Progression of Coronary Calcium and Incident Coronary Heart Disease Events: MESA (Multi-Ethnic Study of Atherosclerosis). J Am Coll Cardiol. 2013;61(12):1231-39.
- Grundy SM, Stone NJ, Bailey AL, et al. 2026 ACC/AHA Guideline on the Management of Blood Cholesterol. Circulation. 2026;154(3):e1-e48.
