心率及心律对冠状动脉CTA扫描中智能期相技术准确性的影响

The effect of heart rate and heart rhythm on the accuracy of smart phase technique in coronary computed tomography angiography examination

目的:探讨心率及心律对智能期相技术(smart phase)选取最佳期相准确性的影响。方法:将不同心率(HR)和心律的120例临床疑诊冠心病拟行冠状动脉CTA扫描的患者分为3组:A组40例,HR≤80次/分钟且心律齐;B组40例,HR>80次/分钟且心律齐;C组40例,心律不齐。将智能期相技术选取的最佳期相图像进行后处理,并对图像质量进行客观评价和主观评分。只要有一支冠状动脉的主观评分无法满足诊断要求即判定为智能期相技术不准确,则人工重新选取最佳期相并进行图像后处理。由两位具有五年以上冠脉CTA诊断经验的医师进行图像质量的主观评分,并采用Kappa检验评价两者间的评分一致性。结果:自动期相技术在A组中的准确率为95%(38/40),在B组中的准确率87.5%(35/40),在C组中的准确率为75%(30/40)。三组间智能期相技术准确率的差异有统计学意义(P=0.035)。智能期相技术选择不准确时,经人工重新选取期相后,所有图像均能满足诊断要求,各组间图像质量的主观评分间的差异无统计学意义(P=0.978),两位阅片者间的评分一致性较好(Kappa值=0.77)。结论:高心率及心律不齐会降低冠脉CTA检查中智能期相技术的准确性,配合人工选取法可以获得满足诊断要求的图像质量。

Objective：To evaluate the effect of heart rate （HR） and cardiac rhythm （CR） on the accuracy of smart phase technique （SPT） in coronary computed tomography angiography （CCTA） examination. Methods： 120 patients with suspected coronary artery disease underwent CCTA examination and were divided into 3 groups based on their HR and CR. Group A （n=40）：low HR （HR^80bpm） and normal CR;group g （n=40）：high HR （HR^80bpm） and normal CR; group C （n=40） ：cardiac arrhythmia （n=40）. Smart phase technique （SPT） was used and the imaging data obtained in the optimal R-R phase selected by SPT were postprocessed for displaying coronary artery,and image quality was evaluated ob- jectively and subjectively by two radiologists. For each patient,once one of the 15 segments of coronary artery cannot meet the diagnostic demand in subjective assessment,the phase selected hy SPT was regarded accurate,and then a optimal phase was selected by two radiologists,and the corresponding imaging data were postproecessed and image quality were evaluated. Kappa test was used to analyze the consistence between the scores by the two radiologists. Results：The accuracy of SPT was 95% （38/40） in group A,87.5% （35/40） in group B,and 75% in group C （30/40）. Difference of the accuracy of SPT among the three groups was statistically significant （P=0. 035）. After manual reselection of the phase,all the images in the three groups can meet the diagnostic demand （P=0. 978）. Kappa test revealed a good consistency level between the radiolo- gists （Kappa=0. 77）. Conclusion： High heart rate and cardiac arrhythmia may decrease the accuracy of the smart phase technique in CCTA examination, and the image quality could meet the diagnostic demand with manual reselection of the phase.