320排动态容积CT评估钙化斑块对诊断冠状动脉狭窄程度的影响

Impact of calcified plaque on the diagnostic accuracy in detecting coronary stenosis using 320-slice MDCT

目的:分析不同程度钙化斑块对320排动态容积CT冠状动脉成像(320-CCTA)评估冠脉狭窄的影响。方法:回顾性分析161例接受320-CCTA检查,并于4周内接受冠状动脉造影(CAG)检查的冠心病疑诊患者的临床资料。以CAG为"金标准",判断320-CCTA诊断伴不同程度钙化斑块冠状动脉狭窄的准确性;对照CAG结果,绘制320-CCTA的受试者工作特征曲线(ROC曲线)并计算曲线下面积(AUC)值。结果:161例320-CCTA图像质量为4分121例(占75.2%),3分40例(占24.8%)。全部病例无阶梯伪影及运动伪影。182(占7.9%)冠脉节段中发现不同程度钙化斑块,其中轻度钙化斑块136(占5.9%)、中度钙化斑块39(占1.7%)、重度钙化斑块7(占0.3%)。320-CCTA诊断冠状动脉狭窄≥50%的敏感性、特异性:非钙化斑组为98.3%、81.3%,混合斑块组为100%、86.2%,轻度钙化78.6%、99.2%,中度钙化90%、86.2%,重度钙化100%、66.7%,其ROC曲线AUC值分别为0.90、0.93、0.89、0.88和0.83。结论:受重度钙化影响,320-CCTA诊断冠脉狭窄≥50%的准确性有所降低,但总体上具有较高的准确性。

Objective：To investigate the diagnostic accuracy of 320-slice dynamic volume coronary CT angiography（320-CCTA） in detecting coronary stenosis and to analyze the impact of coronary calcium in different calcification burden groups.Methods：The retrospective analysis enrolled 161 cases undergoing 320-CCTA and thereafter invasive coronary angiography（CAG） within 4 weeks for suspected coronary artery disease.Compared to CAG,the pretest probability of coronary stenosis was analyzed; the receiver operation characteristic（ROC） curve and area under curve of ROC（AUC） were used for statistical analyses.Results：Of 161 patients,121 cases（75.2%） with optimal imaging quality（scale 4）,40 patients（24.8%） with adequate quality（scale 3）.No any stairstep artifact or motion artifact in all cases.A total of 182（7.9%） segments had some degree of calcification,of all segments,136（5.9%） had lightly calcification,39（1.7%） had moderate calcification,7（0.3%） had severely calcification.The sensitivity and specificity of 320-CCTA for detecting coronary stenosis were at least 50%：noncalcified plaque group（NCP） 98.3%,81.3%,mixture plaque group（MP） 100%,86.2%,lightly calcified plaque group（LCP） 78.6%,99.2%,moderately calcified plaque group（MCP） 90%,86.2%,severely calcified plaque group（SCP） 100%,66.7%,the AUC was 0.90,0.93,0.89,0.88,0.83,respectively.Conclusion：Generally 320-CCTA provides high diagnostic accuracy; but the accuracy will be decreased due to severely calcification.