Can routine chest CT double as a heart risk scan?

Clinical takeaway: When coronary artery calcium is identified on a routine nongated chest CT, clinicians can have greater confidence using that information to refine ASCVD risk assessment and guide lipid-lowering decisions without requiring a repeat dedicated CAC scan.

With roughly 19 million nongated chest CTs performed annually in the US and the 2026 ACC/AHA dyslipidemia guideline now endorsing incidental CAC assessment, these findings support turning existing imaging into a powerful cardiovascular prevention tool.

Researchers analyzed 2,472 MESA* participants without prior cardiovascular disease who underwent same-day nongated chest CT and ECG-gated CAC imaging. The cohort was 53% female and included White, Black, Hispanic/Latino, and Chinese participants.

Nongated CAC showed a clear dose-response relationship with subsequent events after adjustment for traditional risk factors. Compared with CAC of 0, moderate CAC of 100 to 299 was associated with a 167% higher risk of hard coronary heart disease and a 131% higher risk of hard cardiovascular disease. Severe CAC of 300 or greater was associated with a 422% higher coronary risk and a 189% higher cardiovascular risk.

Scores from nongated and gated scans were highly correlated (r=0.96). Clinically substantial category shifts were rare: only 0.1% of participants differed by more than one adjacent CAC category. Predictive performance was also nearly identical, including adjusted discrimination for coronary events (C-statistic, 0.75 for nongated versus 0.74 for gated imaging).

As the authors noted, “Routine nongated chest computed tomography scans serve as a reliable and scalable platform for quantitative CAC-based cardiovascular risk stratification.” They added that broad use of opportunistic CAC assessment could facilitate earlier preventive therapy “without additional cost or radiation exposure.”

The findings provide timely validation for the 2026 ACC/AHA dyslipidemia guideline recommendation supporting use of incidental CAC from nongated CT scans to inform risk stratification and lipid-lowering treatment decisions.

*MESA, Multi-Ethnic Study of Atherosclerosis.

Source: Verghese D, et al. (2026 July 27) Circulation. Predictive Value of Coronary Artery Calcium Score From Nongated Chest CT Scans Compared With Gated Scans and Incidence of Cardiovascular Events