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冠状动脉粥样硬化性心脏病(简称冠心病)是常见的心血管疾病,其发病率及病死率逐年升高。临床上多采用冠状动脉(简称冠脉)造影作为诊断“冠心病”的金标准,但冠脉造影主要反映解剖学改变,存在一定的片面性。核素心肌灌注显像被认为是冠心病的早期诊断、危险度分层、预后判断的有价值的检查方法[1]。其中,门控心肌灌注显像(gated myocardial perfusion imaging,GMPI)可全面提供心肌血流灌注情况、心脏舒缩功能参数,还可通过相位分析获得反映心肌收缩同步性参数[2-3]。笔者拟采用GMPI得到的负荷总积分(summed stress score,SSS)及相位参数评估冠心病患者的冠脉病变程度。
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收集2016年3月至2017年7月因胸痛入我院的确诊或可疑冠心病患者89例,其中男性52例,女性37例,年龄为32~78(53.7±12.9)岁。经冠脉造影确诊冠心病患者52例(59%,冠心病组),即左主干、前降支、回旋支、右冠脉或其主要分支的血管直径狭窄≥50%,其中陈旧性心肌梗死患者4例;冠脉硬化者26例(29%,冠脉硬化组),即上述血管直径狭窄为0~50%;冠脉血管完全正常者11例(12%,正常组)[4]。入选条件:先后行负荷-静息GMPI和冠脉造影,两项检查时间间隔不超过3个月。排除条件:(1)进行过血运重建术;(2)既往有先天性心脏病、瓣膜病、心肌病、心肌桥等可导致心肌缺血、心功能改变的疾病;(3)因心律失常而不能完成GMPI。89例患者的分组及基本临床情况见表 1。本研究已通过我院伦理委员会审批并取得患者及家属知情同意,审批编号:2016-16。
组别 例数(男/女) 年龄/[(x±s)岁] 高血压/% 糖尿病/% 冠心病组 52(32/20) 55.4±11.0 38.5 23.1 冠脉硬化组 26(14/12) 53.5±10.5 34.6 19.2 正常组 11(6/5) 51.5±9.6 27.3 18.2 统计量 0.500a 0.743b 0.522a 0.228a P值 0.779 0.905 0.770 0.892 注:表中,a为χ2值;b为F值;冠脉:冠状动脉。 表 1 89例入组患者的分组及基本临床情况
Table 1. Comparison of the basic clinical situation of 89 cases of patients enrolled
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采用德国西门子公司Symbia T16型双探头SPECT/CT仪。显像剂为郑州原子高科有限公司提供的99Tcm-MIBI(放化纯度>95%,注射剂量为740~1110 MBq)。受检者检查前至少停用β受体阻滞剂、钙拮抗剂、硝酸酯类等影响心率或扩张冠脉的药物24 h。采用两日法在空腹状态下先后行静息及负荷GMPI,负荷GMPI采用分级式次极量踏车运动试验,达到最大心率的85%或患者出现心绞痛、呼吸困难、心律失常、血压下降、心电图ST段下移>1 mm等情况时,即可注射显像剂。图像采集于静脉注射显像剂后90 min进行。采集条件:矩阵64×64,双探头呈90°,共采集180°,6°/帧,每个心动周期采集16帧,40 s/帧。采用Flash三维迭代重建法获得衰减校正及散射校正后的心脏短轴、水平长轴、垂直长轴图像。
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由两位具有主治医师或以上职称的核医学医师独立分析负荷心肌灌注图像,采用17节段目测半定量法得出SSS,如两者意见不同则请第3位医师共同判断。通过Cedars-Sinai定量门控心肌断层显像软件获得静息及负荷状态下的相位参数,即相位直方图带宽(bandwidth, BW)、相位标准差(standard deviation, SD)和熵。
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采用Gensini积分法[5],对冠脉各支病变程度进行定量评定,即每处病变的积分为狭窄程度评分乘以病变部位评分,每例患者的积分为所有病变积分的总和。将积分为0者记为A组,积分大于0者以三分位点(5.2、20.0)分为B、C、D组,即将样本分为积分逐渐增高的4组:A组积分为0,B组为0<积分≤5.2,C组为5.2<积分≤20.0,D组为20.0<积分≤52.0。
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采用SPSS15.0软件进行统计学分析,符合正态分布的计量资料以均数±标准差(x±s)表示,不符合者以中位数(第25百分位数,第75百分位数)[M(P25,P75)]表示。(1)多组间相位参数经数据转换后采用单因素方差分析,SSS的比较采用Kruskal-Wallis检验;(2)相位参数与Gensini积分的相关性采用Pearson积矩相关分析,SSS与Gensini积分的相关性采用Spearman秩相关分析;(3)以Gensini积分为因变量,SSS及相位参数为自变量进行多因素分析,因自变量间存在共线性问题,采用岭回归分析;(4)组内静息、负荷之间的相位参数的比较采用配对t检验。P<0.05为差异有统计学意义。
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52例冠心病患者中单支病变者26例(50%),双支病变者14例(26.9%),三支病变者12例(23.1%)。Gensini积分为4.0~52.0分,其中,24例(46.1%)为4.0~19.5分,21例(40.4%)为20.0~36.0分,7例(13.5%)为36.5~52.0分(表 2)。
病变支数 例数 Gensini积分 4.0~19.5分 20.0~36.0分 36.5~52.0分 单支 26 18 8 0 双支 14 3 11 0 三支 12 03 02 7 表 2 52例冠心病患者的冠状动脉造影结果(例)
Table 2. Coronary angiography of 52 cases of coronary heart disease (case)
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89例患者的Gensini积分为0~52.0分,中位数为9.0分。表 3结果显示,SSS、BW、SD和熵随Gensini积分的增高整体呈上升趋势,除A组与B组之间的差异无统计学意义(统计量分别为-0.191、-1.718、-0.950和-1.646,均P>0.05),其余各组间差异均有统计学意义(统计量范围分别为-5.142~-0.734、-10.403~-5.096、-10.009~-4.697和-8.687~-4.310,均P<0.001)。典型GMPI图像见图 1、图 2。
图 1 冠状动脉血管正常组患者的负荷-静息门控心肌灌注图
Figure 1. Stress and rest GMPI bull's eye plot and phase histogram of a patient in the normal group
图 2 冠心病组患者的负荷-静息门控心肌灌注图像
Figure 2. Stress-rest GMPI bull's plot eye and phase histogram of a patient with coronary heart disease
组别 例数 SSS BW/° SD/° 熵/% A组 11 1(0, 2) 19.5±6.8 05.3±1.7 24.7±5.9 B组 26 1(0, 2) 23.9±7.3 06.7±3.1 28.9±7.9 C组 29 2(1, 3) 41.6±15.2 12.5±6.1 37.1±7.7 D组 23 5(4, 10) 65.8±19.1 21.7±7.0 46.4±5.3 统计量 36.025a 50.050b 42.441b 35.094b P值 <0.001 <0.001 <0.001 <0.001 注:表中,A组~D组分别表示Gensini积分为0、0<积分≤5.2、5.2<积分≤20.0、20.0<积分≤52.0的胸痛患者;SSS:负荷总积分;BW:带宽;SD:标准差;a为χ2值;b为F值。 表 3 门控心肌灌注显像各参数与冠状动脉病变程度的对比
Table 3. Gated myocardial perfusion imaging parameters and the severity of coronary lesions comparedGated myocardial perfusion imaging parameters and the severity of coronary lesions compared
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在冠心病组中,SSS、静息BW、SD、熵与Gensini积分呈正相关(r=0.750、0.747、0.671、0.695,均P<0.05)。而在冠脉硬化组和正常组中,GMPI各参数与Gensini积分无明显相关性。
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对89例患者的岭回归分析结果显示,BW与冠脉病变的关联最明显,其他依次为SSS、熵和SD(t=6.692、3.688、3.559和2.896,均P<0.05)(表 4)。
参数 Beta B SE(B) t值 P值 SSS 0.215 0.647 0.175 3.688 <0.001 BW 0.299 0.180 0.027 6.692 <0.001 SD 0.163 0.268 0.093 2.896 0.005 熵 0.210 0.271 0.076 3.559 <0.001 注:表中,SSS:负荷总积分;BW:带宽;SD:标准差。 表 4 89例患者的门控心肌灌注显像参数与冠状动脉病变程度的多因素分析
Table 4. Multivariate analysis of gated myocardial perfusion imaging parameters and severity of coronary lesions in 89 cases
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SSS及静息BW、SD、熵在冠脉硬化组和正常组间的差异无统计学意义(统计量分别为0.000、1.462、0.812和1.422,均P>0.05),而在冠心病组和冠脉硬化组(统计量分别为-4.415、8.299、8.176和6.752,均P<0.001)、冠心病组和正常组(统计量分别为-3.087、7.591、6.797和6.427,均P<0.001)之间的差异均有统计学意义(表 5)。
组别 例数 Gensini积分 SSS BW/° SD/° 熵/% 冠心病组 52 21.3±12.3 3(1,5) 52.4±20.6 16.7±7.7 41.3±8.0 冠脉硬化组 26 3.4±1.4 1(0, 2) 23.7±7.4 6.4±2.9 28.7±8.0 正常组 11 0 1(0, 2) 19.5±6.8 5.3±1.7 24.7±5.9 统计量 65.819a 24.041a 51.022b 45.776b 35.019b P值 <0.001 <0.001 <0.001 <0.001 <0.001 注:表中,SSS:负荷总积分;BW:带宽;SD:标准差;a为χ2值;冠脉:冠状动脉。 表 5 门控心肌灌注显像各参数在3组间的比较
Table 5. Gated myocardial perfusion imaging parameters of the three groups
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静息与负荷BW(39.9°±22.1°、40.3°±22.9°)、SD(12.3°±8.1°、12.4°±8.2°)、熵(35.6%±10.3%、35.9%±11.0%)之间的差异均无统计学意义(t=0.283、1.121和0.726,均P>0.05)。
门控心肌灌注显像负荷总积分及相位分析对冠状动脉病变程度的评估价值
Assessment of the value of summed stress score and phase analysis of gated myocardial perfusion imaging in the severity of coronary artery lesion
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摘要:
目的探讨门控心肌灌注显像(GMPI)负荷总积分(SSS)及相位分析对冠状动脉(简称冠脉)病变程度的评估价值。 方法入组先后行冠脉造影和99Tcm-甲氧基异丁基异腈两日法负荷-静息GMPI的胸痛患者89例,其中,经冠脉造影确诊冠状动脉粥样硬化性心脏病(简称冠心病)者52例(冠心病组),冠脉硬化者26例(冠脉硬化组),正常者11例(正常组)。冠脉病变程度由Gensini积分表示。采用17节段目测半定量法及定量门控心肌断层显像软件相位分析得出SSS和相位直方图带宽(BW)、相位标准差(SD)和熵,分析上述参数与Gensini积分的相关性,以及在冠心病组、冠脉硬化组及正常组之间的差异。统计学方法采用Kruskal-Wallis检验、单因素方差分析、相关分析、岭回归分析和配对t检验。 结果(1)单因素分析结果显示,在病变程度不同的各组中,Gensini积分随GMPI各参数的增高而逐渐增高。(2)岭回归分析结果显示,BW是反映冠脉病变严重程度最显著的参数,其他依次为SSS、熵和SD(t=6.692、3.688、3.559和2.896,均P<0.05)。(3)冠心病组的SSS和静息BW、SD、熵与Gensini积分呈正相关(r=0.750、0.747、0.671和0.695,均P<0.05)。而冠脉硬化组及正常组的各参数与Gensini积分无明显相关性。冠心病组的静息BW(52.4°±20.6°)、SD(16.7°±7.7°)、熵(41.3%±8.0%)均显著大于冠脉硬化组(23.7°±7.4°、6.4°±2.9°、28.7%±8.0%),差异有统计学意义(F=8.299、8.176、6.752,均P<0.001),但冠脉硬化组与正常组间上述参数的差异均无统计学意义(F=1.462、0.812和1.422,均P>0.05)。89例患者的静息与负荷BW、SD、熵之间的差异均无统计学意义(t=0.283、1.121和0.726,均P>0.05)。 结论SSS、BW、SD、熵在评估冠脉病变程度中具有一定的价值。静息、负荷GMPI相位分析对评价左室收缩同步性的价值相当。 Abstract:ObjectiveTo assesse the value of summed stress score (SSS) and phase analysis of gated myocardial perfusion imaging (GMPI) in the severity of coronary artery lesion. MethodsEighty-nine patients with chest pain who underwent coronary angiography and 99Tcm-methoxyisobutylisonitrile (99Tcm-MIBI) two-day stress-rest GMPI were enrolled in this study. Among them, 52 patients were diagnosed with coronary heart disease by coronary angiography; 26 patients had coronary atherosclerosis and 11 patients were normal. The degree of coronary artery lesion was represented by Gensini score. SSS and phase histogram bandwidth (BW), standard deviation (SD), and entropy were derived using a 17-segment visual semi-quantitative method and the quantitative gated SPECT software phase analysis to analyze the correlation of the parameters with the Gensini score. The differences of the above parameters among coronary heart disease group, coronary artery sclerosis group, and normal group were compared. Kruskal-Wallis test, ANOVA, correlation analysis, ridge regression, and paired t test were used for statistical methods. Results(1) Univariate analysis showed that Gensini score gradually increased with the increase of GMPI parameters. (2)Ridge regression analysis showed that BW was the most significant parameter that reflected the severity of coronary artery lesion, followed by SSS, entropy, and SD(t=6.692, 3.688, 3.559 and 2.896, all P<0.05). (3)SSS, BW, SD, entropy of coronary heart disease group, and Gensini score were positively correlated (r=0.750, 0.747, 0.671 and 0.695, all P<0.05). No significant correlation was found between the parameters and Gensini score in the coronary artery sclerosis and normal groups. Rest GMPI analysis showed that BW(52.4°±20.6°), SD(16.7°±7.7°), and entropy(41.3%±8.0%) in coronary heart disease group were significantly higher than those in the coronary artery sclerosis group (23.7°±7.4°, 6.4°±2.9°, and 28.7%±8.0%, respectively; F=8.299, 8.176 and 6.752, all P<0.001). No significant difference was found in these parameters between coronary artery sclerosis group and normal group (F=1.462, 0.812 and 1.422, all P>0.05). The differences in BW, SD and entropy between rest and stress GMPI in 89 patients were not significantly different (t=0.283, 1.121 and 0.726, all P>0.05). ConclusionsSSS, BW, SD, and entropy have certain value in assessing the degree of coronary artery disease. Rest and stress GMPI have similar values in assessing left ventricular synchrony. -
表 1 89例入组患者的分组及基本临床情况
Table 1. Comparison of the basic clinical situation of 89 cases of patients enrolled
组别 例数(男/女) 年龄/[(x±s)岁] 高血压/% 糖尿病/% 冠心病组 52(32/20) 55.4±11.0 38.5 23.1 冠脉硬化组 26(14/12) 53.5±10.5 34.6 19.2 正常组 11(6/5) 51.5±9.6 27.3 18.2 统计量 0.500a 0.743b 0.522a 0.228a P值 0.779 0.905 0.770 0.892 注:表中,a为χ2值;b为F值;冠脉:冠状动脉。 表 2 52例冠心病患者的冠状动脉造影结果(例)
Table 2. Coronary angiography of 52 cases of coronary heart disease (case)
病变支数 例数 Gensini积分 4.0~19.5分 20.0~36.0分 36.5~52.0分 单支 26 18 8 0 双支 14 3 11 0 三支 12 03 02 7 表 3 门控心肌灌注显像各参数与冠状动脉病变程度的对比
Table 3. Gated myocardial perfusion imaging parameters and the severity of coronary lesions comparedGated myocardial perfusion imaging parameters and the severity of coronary lesions compared
组别 例数 SSS BW/° SD/° 熵/% A组 11 1(0, 2) 19.5±6.8 05.3±1.7 24.7±5.9 B组 26 1(0, 2) 23.9±7.3 06.7±3.1 28.9±7.9 C组 29 2(1, 3) 41.6±15.2 12.5±6.1 37.1±7.7 D组 23 5(4, 10) 65.8±19.1 21.7±7.0 46.4±5.3 统计量 36.025a 50.050b 42.441b 35.094b P值 <0.001 <0.001 <0.001 <0.001 注:表中,A组~D组分别表示Gensini积分为0、0<积分≤5.2、5.2<积分≤20.0、20.0<积分≤52.0的胸痛患者;SSS:负荷总积分;BW:带宽;SD:标准差;a为χ2值;b为F值。 表 4 89例患者的门控心肌灌注显像参数与冠状动脉病变程度的多因素分析
Table 4. Multivariate analysis of gated myocardial perfusion imaging parameters and severity of coronary lesions in 89 cases
参数 Beta B SE(B) t值 P值 SSS 0.215 0.647 0.175 3.688 <0.001 BW 0.299 0.180 0.027 6.692 <0.001 SD 0.163 0.268 0.093 2.896 0.005 熵 0.210 0.271 0.076 3.559 <0.001 注:表中,SSS:负荷总积分;BW:带宽;SD:标准差。 表 5 门控心肌灌注显像各参数在3组间的比较
Table 5. Gated myocardial perfusion imaging parameters of the three groups
组别 例数 Gensini积分 SSS BW/° SD/° 熵/% 冠心病组 52 21.3±12.3 3(1,5) 52.4±20.6 16.7±7.7 41.3±8.0 冠脉硬化组 26 3.4±1.4 1(0, 2) 23.7±7.4 6.4±2.9 28.7±8.0 正常组 11 0 1(0, 2) 19.5±6.8 5.3±1.7 24.7±5.9 统计量 65.819a 24.041a 51.022b 45.776b 35.019b P值 <0.001 <0.001 <0.001 <0.001 <0.001 注:表中,SSS:负荷总积分;BW:带宽;SD:标准差;a为χ2值;冠脉:冠状动脉。 -
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