Application of coronary artery calcium score measurement on coronary CT angiography

Objective To verify the accuracy and the clinical application of the coronary artery calcium score measurement on coronary CT angiography (CCTA). Methods The study enrolled 1093 patients (56.86 ± 9.47 years old, 454 males) who underwent both coronary artery calcium score plain CT and CCTA scans from 2018 to 2019. Calcium volume (CCTA-CV) and Agatston score (CCTA-AS) were both measured from the CCTA images taking the mean aortic attenuation value pluses twice the standard deviation as the calcium detection threshold. Calcium volume (Plain CT-CV) and Agatston score (Plain CT-AS) were also measured on plain CT as the gold standard. Results Pearson correlation analysis showed good correlations between the CCTA-CV and Plain CT- CV in main branches and total volume ( r 2 = 0.96, 0.96, 0.92, 0.93, 0.96 for LM, LAD, LCX, RCA, and total volume, respectively, p s < 0.001). CCTA-AS also correlated linearly with Plain CT-AS with a good correlation coefficient ( r 2 = 0.96, 0.97, 0.93, 0.94, 0.97 for LM, LAD, LCX, RCA, and total Agatston score, respectively, p s < 0.001).Radiation dose were 1.42 ± 0.13 mSv, and 1.87 ± 0.12 mSv for CCTA scan only and for Plain CT + CCTA ( t = -− 11.82, p < 0.001). CCTA missed 35 cases’ calcification with the mean calcium volume = 4.59 mm 3 and mean Agatston score = 2.31, while CCTA also rediscovered 13 cases’ calcification with the mean calcium volume = 3.92 mm 3 and mean Agatston score = 5.21. Agatston grades Kappa between the two methods was 0.864 ( p < 0.001). Additionally, age, male, diabetes mellitus, typical symptoms, smoke, and cerebrovascular disease were the impact factors for both Plain CT-AS and CCTA-AS ( p s < 0.001). Conclusions Calcium volume and Agatston score can be accurately measured from CCTA images only with ~ 25% radiation dose reduction. Even though there were several missing or newly found calcification cases, CCTA-AS could indicate the risk stratification in the clinics.