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Updated: Jan 30, 2026

Identifying Coronary Artery Calcification on Non-gated Computed Tomography Scans
Published on: August 28, 2018
Diagnostic performance of free-breathing coronary computed tomography angiography without heart rate control using
Zhuo Liu1, Zhuolu Zhang1, Nan Hong1
1Department of Radiology, People's Hospital, Peking University, Beijing, 100044, China.
Objectives:
To evaluate the feasibility of coronary computed tomography angiography (CCTA) in patients with free-breathing using 16-cm z-coverage CT with motion correction algorithm.
Methods:
616 patients underwent CCTA without heart rate control. 325 examinations were performed during breath-holding (group A), and the remaining 291 were performed during free-breathing (group B). The image quality scores were defined as 1 (excellent), 2 (good), 3 (adequate), and 4 (poor). 22 patients in group A and 24 in group B underwent invasive coronary angiography (ICA) after CCTA within two weeks. The image quality score, diagnostic accuracy using ICA as reference, signal-to-noise ratio (SNR), and effective dose (ED) were compared between the two groups.
Results:
Mean heart rate during scanning was 70.8 ± 13.8 bpm in group A and 70.7 ± 13.2 bpm in group B (P = .950). No significant differences were observed in SNR and image quality score (1.49 ± 0.62 vs. 1.53 ± 0.67; P = .647) between the breath-holding and free-breathing groups. ED (1.99 ± 0.83 mSv vs. 2.01 ± 0.88 mSv) was not significantly different between the two groups (P = .975). In a segment-based analysis, the sensitivity, specificity and diagnostic accuracy in the detection of coronary stenosis of more than 50% were 82.1%, 96.8% and 92.2%, respectively in the breath-holding group and 82.2%, 96.6% and 92.2%, respectively in the free-breathing group with no significant differences for these parameters between the two groups.
Conclusions:
CCTA for patients without heart rate control and during free-breathing using 16-cm z-coverage CT with motion correction algorithm showed no significant difference in image quality and diagnostic performance compared with CCTA during breath-holding.
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