【作者】 刘蓉；

【导师】 邓又斌；

【作者基本信息】 华中科技大学 ， 影像医学与核医学， 2010， 博士

【摘要】 第一部分实时心肌声学造影评价冠心病患者冠脉狭窄程度对心肌灌注的影响目的初步探讨实时心肌声学造影定量分析冠心病患者冠脉狭窄程度对心肌灌注的影响。方法对40例冠心病患者经静脉给予Sono Vue进行实时心肌声学造影,将左室壁分为18节段,运用Q-analysis软件进行心肌灌注的定量分析。结果(1)在狭窄冠脉供血区域,其中室壁运动异常的节段为114个,无室壁运动异常的节段为393个。有室壁运动异常节段心肌的A值,k值,A×k值[分别为(6.07±3.16)dB,(0.25±0.11)／s,(1.57±1.25)dB／s]均小于无室壁运动异常节段心肌[分别为7.20±3.11)dB,(0.31±0.16)／s,(2.28±1.16)dB／s],差异均有统计学意义(P<0.01)。相应的值进行标化后,室壁运动异常节段心肌的A×k值小于无室壁运动异常节段心肌[(0.13±0.10) vs(0.19±0.16),P<0.01]。(2)狭窄冠脉供血区域且无室壁运动异常节段心肌,根据冠脉狭窄程度分为两组,狭窄≥75%冠脉供血节段心肌共279个,狭窄<75%冠脉供血节段心肌共114个。狭窄≥75%冠脉供血节段心肌的的A×k值小于狭窄<75%冠脉供血节段心肌[(2.14±1.46)dB／s vs(2.62±2.02)dB／s,P<0.01]。而相应的值进行标化后,狭窄≥75%冠脉供血节段心肌的A×k值亦小于狭窄<75%冠脉供血节段心肌[(0.17±0.11) vs(0.23±0.15),P<0.05]。结论冠脉供血狭窄区域伴室壁运动异常节段的心肌血流量低于无室壁运动异常节段心肌,其中无室壁运动区域的心肌血流量与供血冠脉的狭窄程度有关。第二部分实时心肌声学造影与二维应变成像评价心肌梗死患者存活心肌的研究目的初步探讨实时心肌声学造影与二维应变成像评价心肌梗死患者存活心肌的价值。方法20例准备进行血运重建术心肌梗死患者,于术前1周内行实时心肌声学造影检查,心肌灌注结果进行半定量评价：3分为充盈缺损,2分为回声稀疏不均匀及心内膜下充盈缺损,1分为回声均匀性增强；实时心肌声学造影定义心肌灌注记分≤2分为存活心肌,而心肌充盈缺损表示无心肌存活。术后3个月再次进行二维超声心动图检查。室壁运动采用18节段分析,根据术后的室壁运动有否改善分为存活心肌组和无存活心肌组,同时测量术前左室各节段心肌的收缩期纵向峰值应变。结果(1)血运重建术前,二维超声心动图发现共有90个室壁明显发生节段性运动异常,其中有70个室壁的节段性运动异常术后得到改善。(2)血运重建术前,实时心肌声学造影评价存活心肌为65节段,无存活心肌为25节段,敏感性、特异性及准确性分别为93.8%、64%和85.5%。(3)存活心肌组术前心肌收缩期纵向峰值应变明显高于无存活心肌组[(-7.34±5.84)% vs(-2.11±1.66)%,p<0.001]。以术前心肌收缩期纵向峰值应变≤-5.0%作为截断值判断心肌梗死时存活心肌的敏感性为72%,特异性为85%。结论实时心肌声学造影能够准确地预测梗死心肌的存活性；另外,二维应变成像以术前心肌收缩期纵向峰值应变≤-5.0%作为截断值也可以预测梗死心肌的存活性。第三部分实时心肌声学造影结合二维应变成像评价冠状动脉搭桥术后心肌灌注与收缩功能的改变目的初步探讨实时心肌声学造影结合二维应变成像评价冠状动脉搭桥术后心肌灌注与收缩功能的变化。方法20例拟行冠脉搭桥术的冠心病患者,于术前1周及术后2周分别进行实时心肌超声造影检查。于冠状动脉搭桥术前、术后2周及术后3个月分别获取左室心尖四腔、二腔及左心长轴切面的高帧频图像,应用二维应变软件测量各个节段的收缩期纵向峰值应变。结果冠状动脉搭桥术后71.6%的节段心肌灌注较术前明显改善。在术后3个月,心肌灌注改善组的心肌收缩期纵向峰值应变较术前明显改善,差异有统计学意义[(-15.78±5.91)% vs(-10.45±8.31)%,P<0.05]；而心肌灌注无改善组无明显变化,差异无统计学意义[(-10.33±6.53)% vs(-9.41±6.09)%,P>0.05]。结论冠状动脉搭桥术后心肌灌注改善与否可以反映心肌功能恢复的趋势,而二维应变能够动态观察局部心肌功能变化,联合运用两种技术能够更加准确地评价冠状动脉搭桥术的治疗效果。更多还原

【Abstract】 Evaluation of myocardial perfusion and systolic function in patients with coronary artery disease by myocardial contrast echocardiography and two-dimensional strain echocardiographyPART I Evaluation of the impact of the degree of coronary artery stenosis on myocardial perfusion by real-time myocardial contrast echocardiographyObjective We attempted to evaluate the impact of the degree of coronary artery stenosis of coronary artery patients on myocardial perfusion by real-time myocardial contrast echocardiography (MCE).Methods 40 patients underwent intravenous real-time MCE after venous injections of Sono Vue. Left ventricular wall was divided into 18 segments and quantitative analysis was performed by Q-analysis software.Results (1) There were 507 segments subtended by coronary arteries with >50% stenosis, including 114 segments with abnormal wall motion and 393 segments without abnormal wall motion. A, k and the product A×k were significantly lower in segments with abnormal wall motion than those without abnormal wall motion [(6.07±3.16) dB vs (7.20±3.11) dB, P< 0.01; (0.25±0.11)/s vs (0.31±0.16)/s,P<0.01; (1.57±1.25)dB/s vs (2.28±1.16) dB/s, P<0.01==. However, the standardized number of the product A×k was significantly lower in segments with abnormal wall motion than those without abnormal wall motion [(0.13±0.10) vs (0.19±0.16), P<0.01=. (2) Segments with normal wall motion were divided into 2 groups. Group 1 had 279 segments whose flow was subtended by coronary arteries with≥75% stenosis. Group 2 had 114 segments whose flow was subtended by coronary arteries with <75% stenosis. The product A×k in group 1 was lower than that in group 2[(2.14±1.46) dB/s vs (2.62±2.02) dB/s, P<0.01]. At the same time, the standardized number of the product A×k in group 1 was lower than that in group 2[(0.17±0.11) vs (0.23±0.15), P< 0.05=.Conclusions Our present study showed that the product A×k in segments with abnormal wall motion in patients was significantly different from that in segments without abnormal wall motion. The product A×k in segments without abnormal wall motion was related with coronary artery stenosis.PARTⅡEvaluation of real-time myocardial contrast echocardiography and Two-dimensional strain echocardiography on viable myocardium in patients with myocardial infarctionObjective We attempted to evaluate myocardial viability in patients with myocardial infarction with intravenous real-time myocardial contrast echocardiography (RT-MCE) and Two-dimensional strain echocardiography.Methods Intravenous RT-MCE was performed in 20 patients with myocardial infarction before revascularization. Myocardial perfusion was assessed by visual interpretation and divided into 3 conditions:contrast defect=3; partial or reduced opacification or subendocardial contrast defect=2; homogeneous opacification=1, presence of viability was defined as the presence of contrast effect (score≤2). Two-dimensional images were recorded from the left ventricular four-chamber view, two-chamber view and the apical view before and after revascularization, according ventricular wall motion improved after revascularization, which were divided into viable myocardium group and non-viable myocardium group, the peak systolic longitudinal strain was measured in the apical views before operation.Results (1) 90 significantly segmental wall motion abnormality were found by two-dimensional echocardiography before revascularization, including 70 of abnormal segmental wall motion improved post-operation. (2) Viable myocardium group had 65 segments and non-viable myocardium group had 25 segments detected by RT-MCE before revascularization. The sensitivity, specificity and accuracy were 93.8%,64% and 85.5% respectively. (3) The peak systolic longitudinal strain of viable myocardium group were significantly higher than non-viable myocardium group[(-7.34±5.84)% vs (-2.11±1.66)%, p <0.001]. When taking peak systolic longitudinal strain≤-5.0% as a cut-off value for detecting survived myocardium, the sensitivity and specificity were 72% and 85% respectively.Conclusions RT-MCE can accurately assess myocardial viability. At the same time, when taking peak systolic longitudinal strain≤-5.0% as cut-off value can also assess myocardial viability. PART III Assessment of myocardial perfusion and systolic function in patients with coronary artery disease after coronary artery bypass surgery by real-time myocardial contrast echocardiography and two-dimensional strain echocardiographyObjective To assess the clinical application value of myocardial perfusion and systolic function in patients with coronary artery disease after coronary artery bypass surgery using real-time myocardial contrast echocardiography (RT-MCE) combined with two-dimensional strain echocardiography.Methods 20 patients underwent intravenous RT-MCE by venous injections of Sono Vue before and after coronary artery bypass surgery. Two-dimensional images were recorded from the left ventricular four-chamber view, two-chamber view and the apical view before and after two weeks and three months coronary artery bypass surgery, the peak systolic longitudinal strain was measured.Results Myocardial perfusion significantly increased after coronary artery bypass surgery in about 71.6% segments. In the group that myocardial perfusion was improved, the peak systolic longitudinal strain after three months bypass surgery was significantly higher than that before operation [(-15.78±5.91)% vs. (-10.45±8.31)%, P<0.05]. However, the parameters did not change in the group without myocardial perfusion improvement [(-10.33±6.53)% vs. (-9.41±6.09)%, P>0.05].Conclusions Whether or not the improvement of myocardial perfusion can reflect the recovery trend of regional systolic function, and two-dimensional strain echocardiography can observe dynamic change of regional systolic function, combined with the two methods can more accurately assess the treatment results of coronary artery bypass surgery.更多还原