【作者】 延东娥；

【导师】 唐红；

【作者基本信息】 四川大学 ， 内科学， 2007， 硕士

【摘要】 背景左心室收缩功能是评价心脏疾病及其它系统疾病病情严重程度及预后的重要指标之一。二维超声心动图(two-dimension echocardiography，2DE)是目前临床上最常用的心功能评价方法。然而，当患者透声条件差、不能得到满意的超声图像时，2DE测量左心室收缩功能的准确性将减低。自20世纪80年代左心腔声学造影(left ventricular opacification，LVO)技术出现以来，已有不少文献报道LVO能改善心内膜边界显影，但绝大多数研究局限于观察其对心内膜边界显影的改善作用或对心内膜边界改善的程度等。研究LVO改善心内膜显影之后能否提高测量左心室收缩功能的准确性将有重要的临床价值。目的本研究拟采用LVO技术通过给透声条件较差、心内膜边界显示不清的受试者经肘静脉注射左心腔声学造影剂(八氟丙烷人血白蛋白微球注射液)，应用二维超声心尖单平面Simpson法测量造影前、后左心室收缩功能各项参数，包括左心室舒张末容积(end-diastolic volume，EDV)、收缩末容积(end-systolic volume，ESV)、每搏输出量(stroke volume，SV)和射血分数(ejection fraction，EF)，探讨LVO技术对改善心内膜边界显影，提高测量左心室收缩功能准确性的临床价值，为临床准确评价心功能提供客观依据。资料与方法一、研究对象透声条件较差的受试者58例，男17例，女41例，年龄31～70岁，平均56.6±9.0岁。二、仪器和方法1．仪器使用Philips sonos 5500型彩色多普勒超声诊断仪，S3探头，频率1～3MHz。2．声学造影剂左心腔声学造影剂为八氟丙烷人血白蛋白微球注射液，由上海新兴医药股份有限公司提供。3．超声图像的采集由两位经验丰富的高年资超声医生进行图像采集。取标准心尖四腔心或心尖两腔心切面获得较满意的超声图像，保存至少包括1个完整心动周期的动态图像于磁光盘。保持探头位置及声束方向不变，调节超声诊断仪于LVO状态(机械指数MI：0.4)。于左肘静脉建立静脉通道，缓慢注射八氟丙烷人血白蛋白微球注射液，剂量为0.01ml／kg；同样保存造影后至少包括1个完整心动周期的动态图像于磁光盘。4．显影效果分析由两位经验丰富的高年资超声医生半定量评价LVO改善心内膜边界显影的效果。将心尖两腔心或心尖四腔心切面左心室内膜边界分别划分为6个节段。0代表不显影节段，1代表模糊显影节段，2代表完全清晰显影节段。以显影改善率做为评价LVO改善心内膜边界显影效果的半定量指标。显影改善率=(0→1节段数＋0→2节段数＋1→2节段数)／(0节段数＋1节段数)显著显影改善率=(0→2节段数＋1→2节段数)／(0节段数＋1节段数)5．左心室收缩功能参数的测量数据测量由另两位超声医师(甲、乙)采用盲法独立进行。先由甲、乙分别测量造影前、后左心室收缩功能各参数(EDV、ESV、SV和EF)；再由甲在不同时间(间隔3个月)采用同样的方法重复测量上述参数。6．统计学分析所有数据均为计量资料，用均数±标准差(X(?)±S)表示。各组间差异比较用配对T检验；各测值间相关性分析采用直线相关；P<0.05为有统计学意义。比较造影前、后各参数均数值的离散程度。结果58例受试者均符合入选标准；所有受试者注射声学造影剂后均未出现过敏症状。1．显影效果造影前、后0节段数分别为3个、0个，1节段数分别为96个、3个，2节段数分别为249个、345个。造影前不能清楚识别总节段数99个。显影改善率为100％，其中显著显影改善率为96.97％。2．造影前、后左心室收缩功能测值比较(1)观察者甲造影前、后测值比较第1次测量：ESV和EF值差异有统计学意义(P<0.05)；EDV和SV值差异无统计学意义(P>0.05)。第2次测量：ESV、SV和EF值差异有统计学意义(P<0.05)；EDV值差异无统计学意义(P>0.05)。上述两次测量：造影后ESV的均数值小于造影前；SV和EF值大于造影前。(2)观察者乙造影前、后测值比较ESV、SV和EF值差异有统计学意义(P<0.05)；EDV值差异无统计学意义(P>0.05)。造影后ESV的均数值小于造影前；SV和EF值大于造影前。3．重复性检验及一致性评价(1)观察者内重复性检验及一致性评价观察者甲造影前两次测值的比较：EDV、ESV、SV和EF值差异均无统计学意义(P>0.05)；造影前各参数测值间相关性良好(r：0.86～0.93；P<0.05)。造影后两次测值的比较：EDV、ESV、SV和EF值差异亦无统计学意义(P>0.05)；造影后各参数测值间相关性良好(r：0.72～0.92；P<0.05)。(2)观察者间重复性检验及一致性评价造影前测值的比较观察者甲第1次测量和观察者乙测值的比较：EDV、ESV、SV和EF值差异均无统计学意义(P>0.05)；各参数测值间相关性良好(r：0.83～0.91；P<0.05)。观察者甲第2次测量和观察者乙测值的比较：EDV、ESV、SV和EF值差异亦无统计学意义(P>0.05)；各参数测值间相关性良好(r：0.86～0.88；P<0.05)。造影后测值的比较观察者甲第1次测量和观察者乙测值的比较：EDV、ESV、SV和EF值差异均无统计学意义(P>0.05)；各参数测值间相关性良好(r：0.72～0.91；P<0.05)。观察者甲第2次测量和观察者乙测值的比较：EDV、ESV、SV和EF值差异亦无统计学意义(P>0.05)；各参数测值间相关性良好(r：0.77～0.89；P<0.05)。4．造影前、后测值的标准差值分布无论观察者乙还是观察者甲的两次测量，造影后各参数的标准差值均小于造影前；造影后各项测值离散程度均小于造影前。结论1．常规2DE测量的左心室收缩功能较准确，无论观察者内还是观察者间重复性及一致性均较好。2．LVO通过改善左心室内膜边界显影，提高了2DE测量左心室收缩功能的准确性，观察者内和观察者间重复性良好；一致性好。3．LVO改善收缩末期心内膜边界显影效果优于舒张末期。4．ESV值造影后小于造影前，SV和EF值造影后大于造影前；提示常规2DE可能低估了左心室收缩功能。更多还原

【Abstract】 BackgroundLeft ventricular systolic function is one of the major indexes for prognosing the heart diseases. Two dimensional echocardiography(2DE) is the most common way to measure the cardiac function. However, the poor acoustic window worsens the 2DE image and cardiac function measurement. Left ventricular opacification (LVO) could improve ednocardial border developing. It is important to study whether LVO can enhance the accuracy of measuring left ventricular systolic function by improving the endocardial border developing.ObjectiveTo evaluate the value of LVO in enhancing the accuracy of measuring the left ventricular systolic function by improving the endocardial border developing, and to provide an useful way to measure cardiac function accurately.Materials and Methods1. 58 cases with poor acoustic window were studied. Among them, male 17 cases, female 41 cases, age ranged 31 -70yrs old, the mean age 56.6±9.9 years old.2. Standard apical four chamber image is got and recorded in optical disk before and after injection of human albumin microspheres, injectable suspension octafluoropropane formulation.3. Simpson method is adopted for left ventricular systolic function, which include left ventricular end-diastolic volume(EDV), end-systolic volume(ESV), stroke volume(SV) and ejection fraction(EF).All the left ventricular systolic function data before and after injection were measured by 2 doctors separately and blindly. The data was measured again by one of the above 2 doctors 3 months later.4. Left ventricular endocardial border is divided into 6 segments. Score 0: absent segment, score 1: fuzzy segment, score 2: clear segment.Autoradiography improvement rate is used for evaluating the effect of LVO enhancing endocardial border developing.Improvement rate=(segments of 0→1 and (0→2 + segments of 1→2)/ (segments of score 0 + segments of score 1)Significant improvement rate= (segments of 0→2+ segments of 1→2)/(segments of score 0 + segments of score 1)5. Paired t test and linear correlation analysis are adopted.Results1. Autoradiography resultsBefore and after LVO, segments of score 0 are 3 and 0, for score 1: 96 and 3 . for score 2: 249 and 345.Segments of score0 before LVO is 99. Improvement rate is 100%, significant improvement rate is 96.97%. 2. Comparison of left ventricular systolic function before and after LVOThe differences of ESV,SV and EF were statistically significant (P<0.05); EDV was not statistically significant (P>0.05).ESV was smaller after LVO than before;SV and EF were greater after LVO than before. The two doctors got the same results as above.3. Repeatability TestNo matter before or after LVO, the difference of EDV、ESV、SV and EF were not statistically significant(P>0.05) and all parameters were correlative(P<0.05) both inter-observer and inner- observer.4. The standard deviations of parameters were all greater before LVO than after.Conclusions1. 2DE is a relative accurate method of measuring left ventricular systolic function, good consistency and reproducibility is in intra-observers and inter-observers.2. LVO can enhance the accuracy of 2DE in measuring left ventricular systolic function by improving left ventricular endocardial border developing; good consistency and reproducibility is in intra- observers and inter-observers.3. LVO improves end-systolic endocardial border developing better than end-diastole one.4. ESV values is less before LVO than after, however, SV and EF values are larger before LVO than after,which suggests that 2DE may underestimate the left ventricular systolic function.更多还原