电子束CT对冠状动脉钙化的定量研究.doc

电子束CT对冠状动脉钙化的定量研究电子束CT对冠状动脉钙化的定量研究2010-09-07 张少雄戴汝平高润霖何沙吕滨荆宝莲 白桦姚康宝陈纪林杨跃进 【摘要】目的探讨冠状动脉钙化与造影所示冠状动脉狭窄间的关系。方法对218例因临床怀疑或确诊为冠心病而行冠状动脉造影的患者，用电子束CT（EBCT）检查其冠状动脉钙化。结果冠状动脉狭窄组的钙化总积分明显高于非狭窄组（P0.001）,二者积分分别为 229363，42125。冠状动脉狭窄支数与钙化积分呈正相关。全组冠状动脉钙化预测冠心病的总体敏感性、特异性及准确性分别为82、75及79，与老年组相比，年轻组的特异性较高而敏感性较低。结论研究结果提示：EBCT钙化积分是预测冠心病的有价值的指标。 【关键词】冠状动脉疾病钙质沉着症体层摄影术，X线计算机 Quantification analysis of coronary artery calcification by electron beam computed tomography in ChineseZhang Shaoxiong, Dai Ruping, Gao Runlin, et al. Cardiovasclar Institute & Fu Wai Hospital, PUMC & CAMS, Beijing 100037 【Abstract】ObjectiveTo investigate the relationship of coronary artery calcification (CAC) and angiographically significant coronary artery disease. MethodsElectron beam computed tomography (EBCT) was performed for detecting coronary calcification in 218 patients underwent coronary angiography whom were suspected coronary artery disease. Significant coronary artery stenosis was defined as greater than 50% narrowing of lumen. ResultsAmong 135 patients in whom CAC was identified, 86% had angiographically significant coronary stenosis, and 82% of 142 patients with angiographically significant coronary stenosis showed CAC by EBCT. The total scores of CAC in patients with significant coronary artery disease (CAD) demonstrated by angiography were much higher than those in patients without CAD, the scores were 229363, 42125, respectively (P0.001). There was a positive relation between the number of vessels with significant stenosis and the total calcification score, on the other hand, the more the vessels with CAC, the higher the probability of the patients with significant coronary stenosis. The overall sensitivity, specificity and accuracy of CAC for stenosis were 82%, 75% and 79% respectively. In the younger age group the sensitivity was lower and the specificity was generally higher than that in the elderly group. The cutpoint of calcification score for prediciting significant stenosis for 40-49, 50-59 and 60-69 years age group in present study were 1,25 and 50 respectively. ConclusionElectron beam CT calcification score appears to be an effective predictor of coronary artery disease. 【Key words】coronary diseasecalcinosistomography, X-ray computed 冠状动脉钙化是冠状动脉粥样硬化的标志,已为病理学家所证实，因此，检出冠状动脉钙化对于冠心病的诊断具有重要意义。本文旨在利用电子束CT(EBCT)对冠状动脉钙化的定量研究，探讨冠状动脉钙化与冠心病的关系，讨论各年龄组冠状动脉钙化定量预测冠心病的标准，冠状动脉狭窄程度和范围与钙化间的关系，以及冠状动脉钙化的程度及范围与冠状动脉狭窄关系。 资料与方法 1.病人来源：自1995年8月至1996年8月所有经EBCT检查又行冠状动脉造影的患者共218例，其中男性176例，女性42例，年龄自2774岁，平均547岁。其中46例为风湿性心脏病来院行瓣膜置换术，其余患者皆为临床怀疑或确诊冠心病患者。 2.EBCT检查： 图像采集均用Imatron C-150型EBCT机及标准的操作程序进行检查，扫描方式为单层扫描模式。扫描自气管分叉下方2 cm始，根据心脏大小，共扫2030层，层厚为3 mm，包括冠状动脉全程。扫描时间为100毫秒。扫描采用心电门控触发期。 3.EBCT图像处理及冠状动脉钙化积分计算： 钙化灶定义为CT峰值130 HU，面积1 mm2的病灶。钙化积分由CT峰值评分与钙化面积之乘积得出。 CT峰值评分标准如下： 1130199 HU；2200299 HU；3300399 HU；4400 HU。操作者逐层圈出符合上述条件的病灶，由计算机自动得出钙化面积。各支钙化灶积分之和得出该支血管的钙化积分，诸支血管钙化积分之和则为该患者冠状动脉钙化总积分。 我们将冠状动脉分成左主干，前降支，回旋支及右冠脉4个部分来分析冠状动脉钙化情况并与冠状动脉造影作对照。对角支的病变归入前降支，钝缘支的病变归入回旋支，锐缘支的病变则归入右冠脉。 4.冠状动脉造影： 以Judkins法行冠状动脉造影，将冠状动脉直径缩小50者定为冠心病，并据狭窄与否及狭窄程度将冠状动脉病变分成 049，5074，75100三组，分别分析冠状动脉狭窄与钙化间的关系。冠状动脉造影片均经至少两位有经验医生阅片,阅片前均不知 EBCT检查结果。冠状动脉造影与 EBCT检查时间间隔均小于2个月。 5.统计学分析： 按照标准统计学方法对各组数据进行处理，分别计算各组冠状动脉钙化预测冠心病的敏感性，特异性及准确性，并由systat统计学软件及Microsoft Exel统计学软件对各组结果进行处理，对各组定量积分均数进行差别的显著性检验。 结果 1.冠状动脉造影：218例中，有冠状动脉狭窄者共142例，占65；EBCT显示有冠状动脉钙化者135例，占62。全组冠状动脉钙化8