Abstract：Objective To evaluate image quality of coronary CT angiography performed with wide detector CT in patients with
coronary artery bypass graft (CABG) , and to assess the effect of heart rate and heart rate variability on image quality. Methods The
coronary CT images of 107 CABG patients were analyzed retrospectively. Combined with the heart rate, the images were scored
subjectively and evaluated objectively. The objective evaluation was performed by calculating signal noise ratio (SNR) and contrast
to noise ratio (CNR) and CT values. The image quality of bridge vessels was compared between arterial bridge and venous bridge,
and the image quality of proximal, middle and distal vessels of bridge vessels was compared segmentally. Results The subjective
image score of venous bridge was higher than that of arterial bridge, and objective statistical analysis of SNR and CNR showed that
venous bridge was higher than arterial bridge with statistical significance (P<0.05). In the subjective score, the proximal end of
arterial bridge and venous bridge were higher than the middle end, and the proximal end was higher than the distal end, the difference
was statistically significant (P<0.05), while the difference between the middle end and the distal end was not statistically significant
(P>0.05). The objective evaluation showed that there was no significant difference in SNR and CNR between proxial and middle
segments (P＞0.05), proximal segments was significantly higher compared to distal segments, and middle segments was higher
than distal segments (P<0.05). In venous grafts, SNR and CNR in proximal segments was significantly higher compared to middle
segments (P＜0.05), SNR and CNR in middle segments was significantly higher compared to distal segments (P＜0.05). Logistic
regression analysis showed that heart rate was correlated with the subjective score of bypass vessels (OR=0.973, P<0.001, CI:
0.958~0.988), while heart rate change, BMI and age were not correlated with the subjective score. Conclusion In coronary artery
bypass CTA imaging, the heart rate is correlated with the image quality, but the heart rate variability is not correlated with the image
quality. The CTA image quality of venous bridge is better than that of arterial bridge.
王紫薇，赵利娜，王恒，何光锡，帅桃，李真林. 宽体探测器CT在冠状动脉旁路移植术后复查中的应用及图像质量评估[J]. 中国医疗设备, 2021, 36(7): 73-76.
WANG Ziwei, ZHAO Lina, WANG Heng, HE Guangxi, SHUAI Tao, LI Zhenlin. Application and Image Quality Evaluation of Wide Detector CT in
Reexamination After Coronary Artery Bypass Grafts. China Medical Devices, 2021, 36(7): 73-76.
